1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Ada
.Characters
.Latin_1
; use Ada
.Characters
.Latin_1
;
28 with Atree
; use Atree
;
29 with Casing
; use Casing
;
30 with Checks
; use Checks
;
31 with Debug
; use Debug
;
32 with Einfo
; use Einfo
;
33 with Elists
; use Elists
;
34 with Errout
; use Errout
;
36 with Exp_Dist
; use Exp_Dist
;
37 with Exp_Util
; use Exp_Util
;
38 with Expander
; use Expander
;
39 with Freeze
; use Freeze
;
40 with Gnatvsn
; use Gnatvsn
;
41 with Itypes
; use Itypes
;
43 with Lib
.Xref
; use Lib
.Xref
;
44 with Nlists
; use Nlists
;
45 with Nmake
; use Nmake
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
50 with Sdefault
; use Sdefault
;
52 with Sem_Aux
; use Sem_Aux
;
53 with Sem_Cat
; use Sem_Cat
;
54 with Sem_Ch6
; use Sem_Ch6
;
55 with Sem_Ch8
; use Sem_Ch8
;
56 with Sem_Ch10
; use Sem_Ch10
;
57 with Sem_Dim
; use Sem_Dim
;
58 with Sem_Dist
; use Sem_Dist
;
59 with Sem_Elab
; use Sem_Elab
;
60 with Sem_Elim
; use Sem_Elim
;
61 with Sem_Eval
; use Sem_Eval
;
62 with Sem_Prag
; use Sem_Prag
;
63 with Sem_Res
; use Sem_Res
;
64 with Sem_Type
; use Sem_Type
;
65 with Sem_Util
; use Sem_Util
;
67 with Stand
; use Stand
;
68 with Sinfo
; use Sinfo
;
69 with Sinput
; use Sinput
;
71 with Stringt
; use Stringt
;
73 with Stylesw
; use Stylesw
;
74 with Targparm
; use Targparm
;
75 with Ttypes
; use Ttypes
;
76 with Tbuild
; use Tbuild
;
77 with Uintp
; use Uintp
;
78 with Uname
; use Uname
;
79 with Urealp
; use Urealp
;
81 package body Sem_Attr
is
83 True_Value
: constant Uint
:= Uint_1
;
84 False_Value
: constant Uint
:= Uint_0
;
85 -- Synonyms to be used when these constants are used as Boolean values
87 Bad_Attribute
: exception;
88 -- Exception raised if an error is detected during attribute processing,
89 -- used so that we can abandon the processing so we don't run into
90 -- trouble with cascaded errors.
92 -- The following array is the list of attributes defined in the Ada 83 RM.
93 -- In Ada 83 mode, these are the only recognized attributes. In other Ada
94 -- modes all these attributes are recognized, even if removed in Ada 95.
96 Attribute_83
: constant Attribute_Class_Array
:= Attribute_Class_Array
'(
102 Attribute_Constrained |
109 Attribute_First_Bit |
115 Attribute_Leading_Part |
117 Attribute_Machine_Emax |
118 Attribute_Machine_Emin |
119 Attribute_Machine_Mantissa |
120 Attribute_Machine_Overflows |
121 Attribute_Machine_Radix |
122 Attribute_Machine_Rounds |
128 Attribute_Safe_Emax |
129 Attribute_Safe_Large |
130 Attribute_Safe_Small |
133 Attribute_Storage_Size |
135 Attribute_Terminated |
138 Attribute_Width => True,
141 -- The following array is the list of attributes defined in the Ada 2005
142 -- RM which are not defined in Ada 95. These are recognized in Ada 95 mode,
143 -- but in Ada 95 they are considered to be implementation defined.
145 Attribute_05 : constant Attribute_Class_Array := Attribute_Class_Array'(
146 Attribute_Machine_Rounding |
149 Attribute_Stream_Size |
150 Attribute_Wide_Wide_Width
=> True,
153 -- The following array is the list of attributes defined in the Ada 2012
154 -- RM which are not defined in Ada 2005. These are recognized in Ada 95
155 -- and Ada 2005 modes, but are considered to be implementation defined.
157 Attribute_12
: constant Attribute_Class_Array
:= Attribute_Class_Array
'(
158 Attribute_First_Valid |
159 Attribute_Has_Same_Storage |
160 Attribute_Last_Valid |
161 Attribute_Max_Alignment_For_Allocation => True,
164 -- The following array contains all attributes that imply a modification
165 -- of their prefixes or result in an access value. Such prefixes can be
166 -- considered as lvalues.
168 Attribute_Name_Implies_Lvalue_Prefix : constant Attribute_Class_Array :=
169 Attribute_Class_Array'(
174 Attribute_Unchecked_Access |
175 Attribute_Unrestricted_Access
=> True,
178 -----------------------
179 -- Local_Subprograms --
180 -----------------------
182 procedure Eval_Attribute
(N
: Node_Id
);
183 -- Performs compile time evaluation of attributes where possible, leaving
184 -- the Is_Static_Expression/Raises_Constraint_Error flags appropriately
185 -- set, and replacing the node with a literal node if the value can be
186 -- computed at compile time. All static attribute references are folded,
187 -- as well as a number of cases of non-static attributes that can always
188 -- be computed at compile time (e.g. floating-point model attributes that
189 -- are applied to non-static subtypes). Of course in such cases, the
190 -- Is_Static_Expression flag will not be set on the resulting literal.
191 -- Note that the only required action of this procedure is to catch the
192 -- static expression cases as described in the RM. Folding of other cases
193 -- is done where convenient, but some additional non-static folding is in
194 -- Expand_N_Attribute_Reference in cases where this is more convenient.
196 function Is_Anonymous_Tagged_Base
198 Typ
: Entity_Id
) return Boolean;
199 -- For derived tagged types that constrain parent discriminants we build
200 -- an anonymous unconstrained base type. We need to recognize the relation
201 -- between the two when analyzing an access attribute for a constrained
202 -- component, before the full declaration for Typ has been analyzed, and
203 -- where therefore the prefix of the attribute does not match the enclosing
206 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean);
207 -- Rewrites node N with an occurrence of either Standard_False or
208 -- Standard_True, depending on the value of the parameter B. The
209 -- result is marked as a static expression.
211 -----------------------
212 -- Analyze_Attribute --
213 -----------------------
215 procedure Analyze_Attribute
(N
: Node_Id
) is
216 Loc
: constant Source_Ptr
:= Sloc
(N
);
217 Aname
: constant Name_Id
:= Attribute_Name
(N
);
218 P
: constant Node_Id
:= Prefix
(N
);
219 Exprs
: constant List_Id
:= Expressions
(N
);
220 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
225 -- Type of prefix after analysis
227 P_Base_Type
: Entity_Id
;
228 -- Base type of prefix after analysis
230 -----------------------
231 -- Local Subprograms --
232 -----------------------
234 procedure Address_Checks
;
235 -- Semantic checks for valid use of Address attribute. This was made
236 -- a separate routine with the idea of using it for unrestricted access
237 -- which seems like it should follow the same rules, but that turned
238 -- out to be impractical. So now this is only used for Address.
240 procedure Analyze_Access_Attribute
;
241 -- Used for Access, Unchecked_Access, Unrestricted_Access attributes.
242 -- Internally, Id distinguishes which of the three cases is involved.
244 procedure Analyze_Attribute_Old_Result
245 (Legal
: out Boolean;
246 Spec_Id
: out Entity_Id
);
247 -- Common processing for attributes 'Old and 'Result. The routine checks
248 -- that the attribute appears in a postcondition-like aspect or pragma
249 -- associated with a suitable subprogram or a body. Flag Legal is set
250 -- when the above criteria are met. Spec_Id denotes the entity of the
251 -- subprogram [body] or Empty if the attribute is illegal.
253 procedure Bad_Attribute_For_Predicate
;
254 -- Output error message for use of a predicate (First, Last, Range) not
255 -- allowed with a type that has predicates. If the type is a generic
256 -- actual, then the message is a warning, and we generate code to raise
257 -- program error with an appropriate reason. No error message is given
258 -- for internally generated uses of the attributes. This legality rule
259 -- only applies to scalar types.
261 procedure Check_Array_Or_Scalar_Type
;
262 -- Common procedure used by First, Last, Range attribute to check
263 -- that the prefix is a constrained array or scalar type, or a name
264 -- of an array object, and that an argument appears only if appropriate
265 -- (i.e. only in the array case).
267 procedure Check_Array_Type
;
268 -- Common semantic checks for all array attributes. Checks that the
269 -- prefix is a constrained array type or the name of an array object.
270 -- The error message for non-arrays is specialized appropriately.
272 procedure Check_Asm_Attribute
;
273 -- Common semantic checks for Asm_Input and Asm_Output attributes
275 procedure Check_Component
;
276 -- Common processing for Bit_Position, First_Bit, Last_Bit, and
277 -- Position. Checks prefix is an appropriate selected component.
279 procedure Check_Decimal_Fixed_Point_Type
;
280 -- Check that prefix of attribute N is a decimal fixed-point type
282 procedure Check_Dereference
;
283 -- If the prefix of attribute is an object of an access type, then
284 -- introduce an explicit dereference, and adjust P_Type accordingly.
286 procedure Check_Discrete_Type
;
287 -- Verify that prefix of attribute N is a discrete type
290 -- Check that no attribute arguments are present
292 procedure Check_Either_E0_Or_E1
;
293 -- Check that there are zero or one attribute arguments present
296 -- Check that exactly one attribute argument is present
299 -- Check that two attribute arguments are present
301 procedure Check_Enum_Image
;
302 -- If the prefix type of 'Image is an enumeration type, set all its
303 -- literals as referenced, since the image function could possibly end
304 -- up referencing any of the literals indirectly. Same for Enum_Val.
305 -- Set the flag only if the reference is in the main code unit. Same
306 -- restriction when resolving 'Value; otherwise an improperly set
307 -- reference when analyzing an inlined body will lose a proper
308 -- warning on a useless with_clause.
310 procedure Check_First_Last_Valid
;
311 -- Perform all checks for First_Valid and Last_Valid attributes
313 procedure Check_Fixed_Point_Type
;
314 -- Verify that prefix of attribute N is a fixed type
316 procedure Check_Fixed_Point_Type_0
;
317 -- Verify that prefix of attribute N is a fixed type and that
318 -- no attribute expressions are present
320 procedure Check_Floating_Point_Type
;
321 -- Verify that prefix of attribute N is a float type
323 procedure Check_Floating_Point_Type_0
;
324 -- Verify that prefix of attribute N is a float type and that
325 -- no attribute expressions are present
327 procedure Check_Floating_Point_Type_1
;
328 -- Verify that prefix of attribute N is a float type and that
329 -- exactly one attribute expression is present
331 procedure Check_Floating_Point_Type_2
;
332 -- Verify that prefix of attribute N is a float type and that
333 -- two attribute expressions are present
335 procedure Check_SPARK_05_Restriction_On_Attribute
;
336 -- Issue an error in formal mode because attribute N is allowed
338 procedure Check_Integer_Type
;
339 -- Verify that prefix of attribute N is an integer type
341 procedure Check_Modular_Integer_Type
;
342 -- Verify that prefix of attribute N is a modular integer type
344 procedure Check_Not_CPP_Type
;
345 -- Check that P (the prefix of the attribute) is not an CPP type
346 -- for which no Ada predefined primitive is available.
348 procedure Check_Not_Incomplete_Type
;
349 -- Check that P (the prefix of the attribute) is not an incomplete
350 -- type or a private type for which no full view has been given.
352 procedure Check_Object_Reference
(P
: Node_Id
);
353 -- Check that P is an object reference
355 procedure Check_PolyORB_Attribute
;
356 -- Validity checking for PolyORB/DSA attribute
358 procedure Check_Program_Unit
;
359 -- Verify that prefix of attribute N is a program unit
361 procedure Check_Real_Type
;
362 -- Verify that prefix of attribute N is fixed or float type
364 procedure Check_Scalar_Type
;
365 -- Verify that prefix of attribute N is a scalar type
367 procedure Check_Standard_Prefix
;
368 -- Verify that prefix of attribute N is package Standard. Also checks
369 -- that there are no arguments.
371 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
);
372 -- Validity checking for stream attribute. Nam is the TSS name of the
373 -- corresponding possible defined attribute function (e.g. for the
374 -- Read attribute, Nam will be TSS_Stream_Read).
376 procedure Check_System_Prefix
;
377 -- Verify that prefix of attribute N is package System
379 procedure Check_Task_Prefix
;
380 -- Verify that prefix of attribute N is a task or task type
382 procedure Check_Type
;
383 -- Verify that the prefix of attribute N is a type
385 procedure Check_Unit_Name
(Nod
: Node_Id
);
386 -- Check that Nod is of the form of a library unit name, i.e that
387 -- it is an identifier, or a selected component whose prefix is
388 -- itself of the form of a library unit name. Note that this is
389 -- quite different from Check_Program_Unit, since it only checks
390 -- the syntactic form of the name, not the semantic identity. This
391 -- is because it is used with attributes (Elab_Body, Elab_Spec and
392 -- Elaborated) which can refer to non-visible unit.
394 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
);
395 pragma No_Return
(Error_Attr
);
396 procedure Error_Attr
;
397 pragma No_Return
(Error_Attr
);
398 -- Posts error using Error_Msg_N at given node, sets type of attribute
399 -- node to Any_Type, and then raises Bad_Attribute to avoid any further
400 -- semantic processing. The message typically contains a % insertion
401 -- character which is replaced by the attribute name. The call with
402 -- no arguments is used when the caller has already generated the
403 -- required error messages.
405 procedure Error_Attr_P
(Msg
: String);
406 pragma No_Return
(Error_Attr
);
407 -- Like Error_Attr, but error is posted at the start of the prefix
409 procedure Legal_Formal_Attribute
;
410 -- Common processing for attributes Definite and Has_Discriminants.
411 -- Checks that prefix is generic indefinite formal type.
413 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
414 -- Common processing for attributes Max_Alignment_For_Allocation and
415 -- Max_Size_In_Storage_Elements.
418 -- Common processing for attributes Max and Min
420 procedure Standard_Attribute
(Val
: Int
);
421 -- Used to process attributes whose prefix is package Standard which
422 -- yield values of type Universal_Integer. The attribute reference
423 -- node is rewritten with an integer literal of the given value which
424 -- is marked as static.
426 procedure Uneval_Old_Msg
;
427 -- Called when Loop_Entry or Old is used in a potentially unevaluated
428 -- expression. Generates appropriate message or warning depending on
429 -- the setting of Opt.Uneval_Old (or flags in an N_Aspect_Specification
430 -- node in the aspect case).
432 procedure Unexpected_Argument
(En
: Node_Id
);
433 -- Signal unexpected attribute argument (En is the argument)
435 procedure Validate_Non_Static_Attribute_Function_Call
;
436 -- Called when processing an attribute that is a function call to a
437 -- non-static function, i.e. an attribute function that either takes
438 -- non-scalar arguments or returns a non-scalar result. Verifies that
439 -- such a call does not appear in a preelaborable context.
445 procedure Address_Checks
is
447 -- An Address attribute created by expansion is legal even when it
448 -- applies to other entity-denoting expressions.
450 if not Comes_From_Source
(N
) then
453 -- Address attribute on a protected object self reference is legal
455 elsif Is_Protected_Self_Reference
(P
) then
458 -- Address applied to an entity
460 elsif Is_Entity_Name
(P
) then
462 Ent
: constant Entity_Id
:= Entity
(P
);
465 if Is_Subprogram
(Ent
) then
466 Set_Address_Taken
(Ent
);
467 Kill_Current_Values
(Ent
);
469 -- An Address attribute is accepted when generated by the
470 -- compiler for dispatching operation, and an error is
471 -- issued once the subprogram is frozen (to avoid confusing
472 -- errors about implicit uses of Address in the dispatch
473 -- table initialization).
475 if Has_Pragma_Inline_Always
(Entity
(P
))
476 and then Comes_From_Source
(P
)
479 ("prefix of % attribute cannot be Inline_Always "
482 -- It is illegal to apply 'Address to an intrinsic
483 -- subprogram. This is now formalized in AI05-0095.
484 -- In an instance, an attempt to obtain 'Address of an
485 -- intrinsic subprogram (e.g the renaming of a predefined
486 -- operator that is an actual) raises Program_Error.
488 elsif Convention
(Ent
) = Convention_Intrinsic
then
491 Make_Raise_Program_Error
(Loc
,
492 Reason
=> PE_Address_Of_Intrinsic
));
495 Error_Msg_Name_1
:= Aname
;
497 ("cannot take % of intrinsic subprogram", N
);
500 -- Issue an error if prefix denotes an eliminated subprogram
503 Check_For_Eliminated_Subprogram
(P
, Ent
);
506 -- Object or label reference
508 elsif Is_Object
(Ent
) or else Ekind
(Ent
) = E_Label
then
509 Set_Address_Taken
(Ent
);
511 -- Deal with No_Implicit_Aliasing restriction
513 if Restriction_Check_Required
(No_Implicit_Aliasing
) then
514 if not Is_Aliased_View
(P
) then
515 Check_Restriction
(No_Implicit_Aliasing
, P
);
517 Check_No_Implicit_Aliasing
(P
);
521 -- If we have an address of an object, and the attribute
522 -- comes from source, then set the object as potentially
523 -- source modified. We do this because the resulting address
524 -- can potentially be used to modify the variable and we
525 -- might not detect this, leading to some junk warnings.
527 Set_Never_Set_In_Source
(Ent
, False);
529 -- Allow Address to be applied to task or protected type,
530 -- returning null address (what is that about???)
532 elsif (Is_Concurrent_Type
(Etype
(Ent
))
533 and then Etype
(Ent
) = Base_Type
(Ent
))
534 or else Ekind
(Ent
) = E_Package
535 or else Is_Generic_Unit
(Ent
)
538 New_Occurrence_Of
(RTE
(RE_Null_Address
), Sloc
(N
)));
540 -- Anything else is illegal
543 Error_Attr
("invalid prefix for % attribute", P
);
549 elsif Is_Object_Reference
(P
) then
552 -- Subprogram called using dot notation
554 elsif Nkind
(P
) = N_Selected_Component
555 and then Is_Subprogram
(Entity
(Selector_Name
(P
)))
559 -- What exactly are we allowing here ??? and is this properly
560 -- documented in the sinfo documentation for this node ???
562 elsif Relaxed_RM_Semantics
563 and then Nkind
(P
) = N_Attribute_Reference
567 -- All other non-entity name cases are illegal
570 Error_Attr
("invalid prefix for % attribute", P
);
574 ------------------------------
575 -- Analyze_Access_Attribute --
576 ------------------------------
578 procedure Analyze_Access_Attribute
is
579 Acc_Type
: Entity_Id
;
584 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
;
585 -- Build an access-to-object type whose designated type is DT,
586 -- and whose Ekind is appropriate to the attribute type. The
587 -- type that is constructed is returned as the result.
589 procedure Build_Access_Subprogram_Type
(P
: Node_Id
);
590 -- Build an access to subprogram whose designated type is the type of
591 -- the prefix. If prefix is overloaded, so is the node itself. The
592 -- result is stored in Acc_Type.
594 function OK_Self_Reference
return Boolean;
595 -- An access reference whose prefix is a type can legally appear
596 -- within an aggregate, where it is obtained by expansion of
597 -- a defaulted aggregate. The enclosing aggregate that contains
598 -- the self-referenced is flagged so that the self-reference can
599 -- be expanded into a reference to the target object (see exp_aggr).
601 ------------------------------
602 -- Build_Access_Object_Type --
603 ------------------------------
605 function Build_Access_Object_Type
(DT
: Entity_Id
) return Entity_Id
is
606 Typ
: constant Entity_Id
:=
608 (E_Access_Attribute_Type
, Current_Scope
, Loc
, 'A');
610 Set_Etype
(Typ
, Typ
);
612 Set_Associated_Node_For_Itype
(Typ
, N
);
613 Set_Directly_Designated_Type
(Typ
, DT
);
615 end Build_Access_Object_Type
;
617 ----------------------------------
618 -- Build_Access_Subprogram_Type --
619 ----------------------------------
621 procedure Build_Access_Subprogram_Type
(P
: Node_Id
) is
622 Index
: Interp_Index
;
625 procedure Check_Local_Access
(E
: Entity_Id
);
626 -- Deal with possible access to local subprogram. If we have such
627 -- an access, we set a flag to kill all tracked values on any call
628 -- because this access value may be passed around, and any called
629 -- code might use it to access a local procedure which clobbers a
630 -- tracked value. If the scope is a loop or block, indicate that
631 -- value tracking is disabled for the enclosing subprogram.
633 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
;
634 -- Distinguish between access to regular/protected subprograms
636 ------------------------
637 -- Check_Local_Access --
638 ------------------------
640 procedure Check_Local_Access
(E
: Entity_Id
) is
642 if not Is_Library_Level_Entity
(E
) then
643 Set_Suppress_Value_Tracking_On_Call
(Current_Scope
);
644 Set_Suppress_Value_Tracking_On_Call
645 (Nearest_Dynamic_Scope
(Current_Scope
));
647 end Check_Local_Access
;
653 function Get_Kind
(E
: Entity_Id
) return Entity_Kind
is
655 if Convention
(E
) = Convention_Protected
then
656 return E_Access_Protected_Subprogram_Type
;
658 return E_Access_Subprogram_Type
;
662 -- Start of processing for Build_Access_Subprogram_Type
665 -- In the case of an access to subprogram, use the name of the
666 -- subprogram itself as the designated type. Type-checking in
667 -- this case compares the signatures of the designated types.
669 -- Note: This fragment of the tree is temporarily malformed
670 -- because the correct tree requires an E_Subprogram_Type entity
671 -- as the designated type. In most cases this designated type is
672 -- later overridden by the semantics with the type imposed by the
673 -- context during the resolution phase. In the specific case of
674 -- the expression Address!(Prim'Unrestricted_Access), used to
675 -- initialize slots of dispatch tables, this work will be done by
676 -- the expander (see Exp_Aggr).
678 -- The reason to temporarily add this kind of node to the tree
679 -- instead of a proper E_Subprogram_Type itype, is the following:
680 -- in case of errors found in the source file we report better
681 -- error messages. For example, instead of generating the
684 -- "expected access to subprogram with profile
685 -- defined at line X"
687 -- we currently generate:
689 -- "expected access to function Z defined at line X"
691 Set_Etype
(N
, Any_Type
);
693 if not Is_Overloaded
(P
) then
694 Check_Local_Access
(Entity
(P
));
696 if not Is_Intrinsic_Subprogram
(Entity
(P
)) then
697 Acc_Type
:= Create_Itype
(Get_Kind
(Entity
(P
)), N
);
698 Set_Is_Public
(Acc_Type
, False);
699 Set_Etype
(Acc_Type
, Acc_Type
);
700 Set_Convention
(Acc_Type
, Convention
(Entity
(P
)));
701 Set_Directly_Designated_Type
(Acc_Type
, Entity
(P
));
702 Set_Etype
(N
, Acc_Type
);
703 Freeze_Before
(N
, Acc_Type
);
707 Get_First_Interp
(P
, Index
, It
);
708 while Present
(It
.Nam
) loop
709 Check_Local_Access
(It
.Nam
);
711 if not Is_Intrinsic_Subprogram
(It
.Nam
) then
712 Acc_Type
:= Create_Itype
(Get_Kind
(It
.Nam
), N
);
713 Set_Is_Public
(Acc_Type
, False);
714 Set_Etype
(Acc_Type
, Acc_Type
);
715 Set_Convention
(Acc_Type
, Convention
(It
.Nam
));
716 Set_Directly_Designated_Type
(Acc_Type
, It
.Nam
);
717 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
718 Freeze_Before
(N
, Acc_Type
);
721 Get_Next_Interp
(Index
, It
);
725 -- Cannot be applied to intrinsic. Looking at the tests above,
726 -- the only way Etype (N) can still be set to Any_Type is if
727 -- Is_Intrinsic_Subprogram was True for some referenced entity.
729 if Etype
(N
) = Any_Type
then
730 Error_Attr_P
("prefix of % attribute cannot be intrinsic");
732 end Build_Access_Subprogram_Type
;
734 ----------------------
735 -- OK_Self_Reference --
736 ----------------------
738 function OK_Self_Reference
return Boolean is
745 (Nkind
(Par
) = N_Component_Association
746 or else Nkind
(Par
) in N_Subexpr
)
748 if Nkind_In
(Par
, N_Aggregate
, N_Extension_Aggregate
) then
749 if Etype
(Par
) = Typ
then
750 Set_Has_Self_Reference
(Par
);
758 -- No enclosing aggregate, or not a self-reference
761 end OK_Self_Reference
;
763 -- Start of processing for Analyze_Access_Attribute
766 Check_SPARK_05_Restriction_On_Attribute
;
769 if Nkind
(P
) = N_Character_Literal
then
771 ("prefix of % attribute cannot be enumeration literal");
774 -- Case of access to subprogram
776 if Is_Entity_Name
(P
) and then Is_Overloadable
(Entity
(P
)) then
777 if Has_Pragma_Inline_Always
(Entity
(P
)) then
779 ("prefix of % attribute cannot be Inline_Always subprogram");
781 elsif Aname
= Name_Unchecked_Access
then
782 Error_Attr
("attribute% cannot be applied to a subprogram", P
);
785 -- Issue an error if the prefix denotes an eliminated subprogram
787 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
789 -- Check for obsolescent subprogram reference
791 Check_Obsolescent_2005_Entity
(Entity
(P
), P
);
793 -- Build the appropriate subprogram type
795 Build_Access_Subprogram_Type
(P
);
797 -- For P'Access or P'Unrestricted_Access, where P is a nested
798 -- subprogram, we might be passing P to another subprogram (but we
799 -- don't check that here), which might call P. P could modify
800 -- local variables, so we need to kill current values. It is
801 -- important not to do this for library-level subprograms, because
802 -- Kill_Current_Values is very inefficient in the case of library
803 -- level packages with lots of tagged types.
805 if Is_Library_Level_Entity
(Entity
(Prefix
(N
))) then
808 -- Do not kill values on nodes initializing dispatch tables
809 -- slots. The construct Prim_Ptr!(Prim'Unrestricted_Access)
810 -- is currently generated by the expander only for this
811 -- purpose. Done to keep the quality of warnings currently
812 -- generated by the compiler (otherwise any declaration of
813 -- a tagged type cleans constant indications from its scope).
815 elsif Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
816 and then (Etype
(Parent
(N
)) = RTE
(RE_Prim_Ptr
)
818 Etype
(Parent
(N
)) = RTE
(RE_Size_Ptr
))
819 and then Is_Dispatching_Operation
820 (Directly_Designated_Type
(Etype
(N
)))
828 -- In the static elaboration model, treat the attribute reference
829 -- as a call for elaboration purposes. Suppress this treatment
830 -- under debug flag. In any case, we are all done.
832 if not Dynamic_Elaboration_Checks
and not Debug_Flag_Dot_UU
then
838 -- Component is an operation of a protected type
840 elsif Nkind
(P
) = N_Selected_Component
841 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
843 if Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
then
844 Error_Attr_P
("prefix of % attribute must be subprogram");
847 Build_Access_Subprogram_Type
(Selector_Name
(P
));
851 -- Deal with incorrect reference to a type, but note that some
852 -- accesses are allowed: references to the current type instance,
853 -- or in Ada 2005 self-referential pointer in a default-initialized
856 if Is_Entity_Name
(P
) then
859 -- The reference may appear in an aggregate that has been expanded
860 -- into a loop. Locate scope of type definition, if any.
862 Scop
:= Current_Scope
;
863 while Ekind
(Scop
) = E_Loop
loop
864 Scop
:= Scope
(Scop
);
867 if Is_Type
(Typ
) then
869 -- OK if we are within the scope of a limited type
870 -- let's mark the component as having per object constraint
872 if Is_Anonymous_Tagged_Base
(Scop
, Typ
) then
880 Q
: Node_Id
:= Parent
(N
);
884 and then Nkind
(Q
) /= N_Component_Declaration
890 Set_Has_Per_Object_Constraint
891 (Defining_Identifier
(Q
), True);
895 if Nkind
(P
) = N_Expanded_Name
then
897 ("current instance prefix must be a direct name", P
);
900 -- If a current instance attribute appears in a component
901 -- constraint it must appear alone; other contexts (spec-
902 -- expressions, within a task body) are not subject to this
905 if not In_Spec_Expression
906 and then not Has_Completion
(Scop
)
908 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
909 N_Index_Or_Discriminant_Constraint
)
912 ("current instance attribute must appear alone", N
);
915 if Is_CPP_Class
(Root_Type
(Typ
)) then
917 ("??current instance unsupported for derivations of "
918 & "'C'P'P types", N
);
921 -- OK if we are in initialization procedure for the type
922 -- in question, in which case the reference to the type
923 -- is rewritten as a reference to the current object.
925 elsif Ekind
(Scop
) = E_Procedure
926 and then Is_Init_Proc
(Scop
)
927 and then Etype
(First_Formal
(Scop
)) = Typ
930 Make_Attribute_Reference
(Loc
,
931 Prefix
=> Make_Identifier
(Loc
, Name_uInit
),
932 Attribute_Name
=> Name_Unrestricted_Access
));
936 -- OK if a task type, this test needs sharpening up ???
938 elsif Is_Task_Type
(Typ
) then
941 -- OK if self-reference in an aggregate in Ada 2005, and
942 -- the reference comes from a copied default expression.
944 -- Note that we check legality of self-reference even if the
945 -- expression comes from source, e.g. when a single component
946 -- association in an aggregate has a box association.
948 elsif Ada_Version
>= Ada_2005
949 and then OK_Self_Reference
953 -- OK if reference to current instance of a protected object
955 elsif Is_Protected_Self_Reference
(P
) then
958 -- Otherwise we have an error case
961 Error_Attr
("% attribute cannot be applied to type", P
);
967 -- If we fall through, we have a normal access to object case
969 -- Unrestricted_Access is (for now) legal wherever an allocator would
970 -- be legal, so its Etype is set to E_Allocator. The expected type
971 -- of the other attributes is a general access type, and therefore
972 -- we label them with E_Access_Attribute_Type.
974 if not Is_Overloaded
(P
) then
975 Acc_Type
:= Build_Access_Object_Type
(P_Type
);
976 Set_Etype
(N
, Acc_Type
);
980 Index
: Interp_Index
;
983 Set_Etype
(N
, Any_Type
);
984 Get_First_Interp
(P
, Index
, It
);
985 while Present
(It
.Typ
) loop
986 Acc_Type
:= Build_Access_Object_Type
(It
.Typ
);
987 Add_One_Interp
(N
, Acc_Type
, Acc_Type
);
988 Get_Next_Interp
(Index
, It
);
993 -- Special cases when we can find a prefix that is an entity name
1002 if Is_Entity_Name
(PP
) then
1005 -- If we have an access to an object, and the attribute
1006 -- comes from source, then set the object as potentially
1007 -- source modified. We do this because the resulting access
1008 -- pointer can be used to modify the variable, and we might
1009 -- not detect this, leading to some junk warnings.
1011 -- We only do this for source references, since otherwise
1012 -- we can suppress warnings, e.g. from the unrestricted
1013 -- access generated for validity checks in -gnatVa mode.
1015 if Comes_From_Source
(N
) then
1016 Set_Never_Set_In_Source
(Ent
, False);
1019 -- Mark entity as address taken, and kill current values
1021 Set_Address_Taken
(Ent
);
1022 Kill_Current_Values
(Ent
);
1025 elsif Nkind_In
(PP
, N_Selected_Component
,
1026 N_Indexed_Component
)
1036 -- Check for aliased view.. We allow a nonaliased prefix when within
1037 -- an instance because the prefix may have been a tagged formal
1038 -- object, which is defined to be aliased even when the actual
1039 -- might not be (other instance cases will have been caught in the
1040 -- generic). Similarly, within an inlined body we know that the
1041 -- attribute is legal in the original subprogram, and therefore
1042 -- legal in the expansion.
1044 if not Is_Aliased_View
(P
)
1045 and then not In_Instance
1046 and then not In_Inlined_Body
1047 and then Comes_From_Source
(N
)
1049 -- Here we have a non-aliased view. This is illegal unless we
1050 -- have the case of Unrestricted_Access, where for now we allow
1051 -- this (we will reject later if expected type is access to an
1052 -- unconstrained array with a thin pointer).
1054 -- No need for an error message on a generated access reference
1055 -- for the controlling argument in a dispatching call: error will
1056 -- be reported when resolving the call.
1058 if Aname
/= Name_Unrestricted_Access
then
1059 Error_Attr_P
("prefix of % attribute must be aliased");
1060 Check_No_Implicit_Aliasing
(P
);
1062 -- For Unrestricted_Access, record that prefix is not aliased
1063 -- to simplify legality check later on.
1066 Set_Non_Aliased_Prefix
(N
);
1069 -- If we have an aliased view, and we have Unrestricted_Access, then
1070 -- output a warning that Unchecked_Access would have been fine, and
1071 -- change the node to be Unchecked_Access.
1074 -- For now, hold off on this change ???
1078 end Analyze_Access_Attribute
;
1080 ----------------------------------
1081 -- Analyze_Attribute_Old_Result --
1082 ----------------------------------
1084 procedure Analyze_Attribute_Old_Result
1085 (Legal
: out Boolean;
1086 Spec_Id
: out Entity_Id
)
1088 procedure Check_Placement_In_Check
(Prag
: Node_Id
);
1089 -- Verify that the attribute appears within pragma Check that mimics
1092 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
);
1093 -- Verify that the attribute appears within a consequence of aspect
1094 -- or pragma Contract_Cases denoted by Prag.
1096 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
);
1097 -- Verify that the attribute appears within the "Ensures" argument of
1098 -- aspect or pragma Test_Case denoted by Prag.
1102 Encl_Nod
: Node_Id
) return Boolean;
1103 -- Subsidiary to Check_Placemenet_In_XXX. Determine whether arbitrary
1104 -- node Nod is within enclosing node Encl_Nod.
1106 procedure Placement_Error
;
1107 -- Emit a general error when the attributes does not appear in a
1108 -- postcondition-like aspect or pragma.
1110 ------------------------------
1111 -- Check_Placement_In_Check --
1112 ------------------------------
1114 procedure Check_Placement_In_Check
(Prag
: Node_Id
) is
1115 Args
: constant List_Id
:= Pragma_Argument_Associations
(Prag
);
1116 Nam
: constant Name_Id
:= Chars
(Get_Pragma_Arg
(First
(Args
)));
1119 -- The "Name" argument of pragma Check denotes a postcondition
1121 if Nam_In
(Nam
, Name_Post
,
1128 -- Otherwise the placement of the attribute is illegal
1133 end Check_Placement_In_Check
;
1135 ---------------------------------------
1136 -- Check_Placement_In_Contract_Cases --
1137 ---------------------------------------
1139 procedure Check_Placement_In_Contract_Cases
(Prag
: Node_Id
) is
1145 -- Obtain the argument of the aspect or pragma
1147 if Nkind
(Prag
) = N_Aspect_Specification
then
1150 Arg
:= First
(Pragma_Argument_Associations
(Prag
));
1153 Cases
:= Expression
(Arg
);
1155 if Present
(Component_Associations
(Cases
)) then
1156 CCase
:= First
(Component_Associations
(Cases
));
1157 while Present
(CCase
) loop
1159 -- Detect whether the attribute appears within the
1160 -- consequence of the current contract case.
1162 if Nkind
(CCase
) = N_Component_Association
1163 and then Is_Within
(N
, Expression
(CCase
))
1172 -- Otherwise aspect or pragma Contract_Cases is either malformed
1173 -- or the attribute does not appear within a consequence.
1176 ("attribute % must appear in the consequence of a contract case",
1178 end Check_Placement_In_Contract_Cases
;
1180 ----------------------------------
1181 -- Check_Placement_In_Test_Case --
1182 ----------------------------------
1184 procedure Check_Placement_In_Test_Case
(Prag
: Node_Id
) is
1185 Arg
: constant Node_Id
:=
1188 Arg_Nam
=> Name_Ensures
,
1189 From_Aspect
=> Nkind
(Prag
) = N_Aspect_Specification
);
1192 -- Detect whether the attribute appears within the "Ensures"
1193 -- expression of aspect or pragma Test_Case.
1195 if Present
(Arg
) and then Is_Within
(N
, Arg
) then
1200 ("attribute % must appear in the ensures expression of a "
1203 end Check_Placement_In_Test_Case
;
1211 Encl_Nod
: Node_Id
) return Boolean
1217 while Present
(Par
) loop
1218 if Par
= Encl_Nod
then
1221 -- Prevent the search from going too far
1223 elsif Is_Body_Or_Package_Declaration
(Par
) then
1227 Par
:= Parent
(Par
);
1233 ---------------------
1234 -- Placement_Error --
1235 ---------------------
1237 procedure Placement_Error
is
1239 if Aname
= Name_Old
then
1240 Error_Attr
("attribute % can only appear in postcondition", P
);
1242 -- Specialize the error message for attribute 'Result
1246 ("attribute % can only appear in postcondition of function",
1249 end Placement_Error
;
1255 Subp_Decl
: Node_Id
;
1257 -- Start of processing for Analyze_Attribute_Old_Result
1260 -- Assume that the attribute is illegal
1265 -- Traverse the parent chain to find the aspect or pragma where the
1266 -- attribute resides.
1269 while Present
(Prag
) loop
1270 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1273 -- Prevent the search from going too far
1275 elsif Is_Body_Or_Package_Declaration
(Prag
) then
1279 Prag
:= Parent
(Prag
);
1282 -- The attribute is allowed to appear only in postcondition-like
1283 -- aspects or pragmas.
1285 if Nkind_In
(Prag
, N_Aspect_Specification
, N_Pragma
) then
1286 if Nkind
(Prag
) = N_Aspect_Specification
then
1287 Prag_Nam
:= Chars
(Identifier
(Prag
));
1289 Prag_Nam
:= Pragma_Name
(Prag
);
1292 if Prag_Nam
= Name_Check
then
1293 Check_Placement_In_Check
(Prag
);
1295 elsif Prag_Nam
= Name_Contract_Cases
then
1296 Check_Placement_In_Contract_Cases
(Prag
);
1298 -- Attribute 'Result is allowed to appear in aspect or pragma
1299 -- [Refined_]Depends (SPARK RM 6.1.5(11)).
1301 elsif Nam_In
(Prag_Nam
, Name_Depends
, Name_Refined_Depends
)
1302 and then Aname
= Name_Result
1306 elsif Nam_In
(Prag_Nam
, Name_Post
,
1313 elsif Prag_Nam
= Name_Test_Case
then
1314 Check_Placement_In_Test_Case
(Prag
);
1321 -- Otherwise the placement of the attribute is illegal
1328 -- Find the related subprogram subject to the aspect or pragma
1330 if Nkind
(Prag
) = N_Aspect_Specification
then
1331 Subp_Decl
:= Parent
(Prag
);
1333 Subp_Decl
:= Find_Related_Declaration_Or_Body
(Prag
);
1336 -- The aspect or pragma where the attribute resides should be
1337 -- associated with a subprogram declaration or a body. If this is not
1338 -- the case, then the aspect or pragma is illegal. Return as analysis
1339 -- cannot be carried out.
1341 if not Nkind_In
(Subp_Decl
, N_Abstract_Subprogram_Declaration
,
1342 N_Entry_Declaration
,
1343 N_Generic_Subprogram_Declaration
,
1345 N_Subprogram_Body_Stub
,
1346 N_Subprogram_Declaration
)
1351 -- If we get here, then the attribute is legal
1354 Spec_Id
:= Unique_Defining_Entity
(Subp_Decl
);
1355 end Analyze_Attribute_Old_Result
;
1357 ---------------------------------
1358 -- Bad_Attribute_For_Predicate --
1359 ---------------------------------
1361 procedure Bad_Attribute_For_Predicate
is
1363 if Is_Scalar_Type
(P_Type
)
1364 and then Comes_From_Source
(N
)
1366 Error_Msg_Name_1
:= Aname
;
1367 Bad_Predicated_Subtype_Use
1368 ("type& has predicates, attribute % not allowed", N
, P_Type
);
1370 end Bad_Attribute_For_Predicate
;
1372 --------------------------------
1373 -- Check_Array_Or_Scalar_Type --
1374 --------------------------------
1376 procedure Check_Array_Or_Scalar_Type
is
1380 -- Dimension number for array attributes
1383 -- Case of string literal or string literal subtype. These cases
1384 -- cannot arise from legal Ada code, but the expander is allowed
1385 -- to generate them. They require special handling because string
1386 -- literal subtypes do not have standard bounds (the whole idea
1387 -- of these subtypes is to avoid having to generate the bounds)
1389 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1390 Set_Etype
(N
, Etype
(First_Index
(P_Base_Type
)));
1395 elsif Is_Scalar_Type
(P_Type
) then
1398 if Present
(E1
) then
1399 Error_Attr
("invalid argument in % attribute", E1
);
1401 Set_Etype
(N
, P_Base_Type
);
1405 -- The following is a special test to allow 'First to apply to
1406 -- private scalar types if the attribute comes from generated
1407 -- code. This occurs in the case of Normalize_Scalars code.
1409 elsif Is_Private_Type
(P_Type
)
1410 and then Present
(Full_View
(P_Type
))
1411 and then Is_Scalar_Type
(Full_View
(P_Type
))
1412 and then not Comes_From_Source
(N
)
1414 Set_Etype
(N
, Implementation_Base_Type
(P_Type
));
1416 -- Array types other than string literal subtypes handled above
1421 -- We know prefix is an array type, or the name of an array
1422 -- object, and that the expression, if present, is static
1423 -- and within the range of the dimensions of the type.
1425 pragma Assert
(Is_Array_Type
(P_Type
));
1426 Index
:= First_Index
(P_Base_Type
);
1430 -- First dimension assumed
1432 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1435 D
:= UI_To_Int
(Intval
(E1
));
1437 for J
in 1 .. D
- 1 loop
1441 Set_Etype
(N
, Base_Type
(Etype
(Index
)));
1442 Set_Etype
(E1
, Standard_Integer
);
1445 end Check_Array_Or_Scalar_Type
;
1447 ----------------------
1448 -- Check_Array_Type --
1449 ----------------------
1451 procedure Check_Array_Type
is
1453 -- Dimension number for array attributes
1456 -- If the type is a string literal type, then this must be generated
1457 -- internally, and no further check is required on its legality.
1459 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
1462 -- If the type is a composite, it is an illegal aggregate, no point
1465 elsif P_Type
= Any_Composite
then
1466 raise Bad_Attribute
;
1469 -- Normal case of array type or subtype
1471 Check_Either_E0_Or_E1
;
1474 if Is_Array_Type
(P_Type
) then
1475 if not Is_Constrained
(P_Type
)
1476 and then Is_Entity_Name
(P
)
1477 and then Is_Type
(Entity
(P
))
1479 -- Note: we do not call Error_Attr here, since we prefer to
1480 -- continue, using the relevant index type of the array,
1481 -- even though it is unconstrained. This gives better error
1482 -- recovery behavior.
1484 Error_Msg_Name_1
:= Aname
;
1486 ("prefix for % attribute must be constrained array", P
);
1489 -- The attribute reference freezes the type, and thus the
1490 -- component type, even if the attribute may not depend on the
1491 -- component. Diagnose arrays with incomplete components now.
1492 -- If the prefix is an access to array, this does not freeze
1493 -- the designated type.
1495 if Nkind
(P
) /= N_Explicit_Dereference
then
1496 Check_Fully_Declared
(Component_Type
(P_Type
), P
);
1499 D
:= Number_Dimensions
(P_Type
);
1502 if Is_Private_Type
(P_Type
) then
1503 Error_Attr_P
("prefix for % attribute may not be private type");
1505 elsif Is_Access_Type
(P_Type
)
1506 and then Is_Array_Type
(Designated_Type
(P_Type
))
1507 and then Is_Entity_Name
(P
)
1508 and then Is_Type
(Entity
(P
))
1510 Error_Attr_P
("prefix of % attribute cannot be access type");
1512 elsif Attr_Id
= Attribute_First
1514 Attr_Id
= Attribute_Last
1516 Error_Attr
("invalid prefix for % attribute", P
);
1519 Error_Attr_P
("prefix for % attribute must be array");
1523 if Present
(E1
) then
1524 Resolve
(E1
, Any_Integer
);
1525 Set_Etype
(E1
, Standard_Integer
);
1527 if not Is_OK_Static_Expression
(E1
)
1528 or else Raises_Constraint_Error
(E1
)
1530 Flag_Non_Static_Expr
1531 ("expression for dimension must be static!", E1
);
1534 elsif UI_To_Int
(Expr_Value
(E1
)) > D
1535 or else UI_To_Int
(Expr_Value
(E1
)) < 1
1537 Error_Attr
("invalid dimension number for array type", E1
);
1541 if (Style_Check
and Style_Check_Array_Attribute_Index
)
1542 and then Comes_From_Source
(N
)
1544 Style
.Check_Array_Attribute_Index
(N
, E1
, D
);
1546 end Check_Array_Type
;
1548 -------------------------
1549 -- Check_Asm_Attribute --
1550 -------------------------
1552 procedure Check_Asm_Attribute
is
1557 -- Check first argument is static string expression
1559 Analyze_And_Resolve
(E1
, Standard_String
);
1561 if Etype
(E1
) = Any_Type
then
1564 elsif not Is_OK_Static_Expression
(E1
) then
1565 Flag_Non_Static_Expr
1566 ("constraint argument must be static string expression!", E1
);
1570 -- Check second argument is right type
1572 Analyze_And_Resolve
(E2
, Entity
(P
));
1574 -- Note: that is all we need to do, we don't need to check
1575 -- that it appears in a correct context. The Ada type system
1576 -- will do that for us.
1578 end Check_Asm_Attribute
;
1580 ---------------------
1581 -- Check_Component --
1582 ---------------------
1584 procedure Check_Component
is
1588 if Nkind
(P
) /= N_Selected_Component
1590 (Ekind
(Entity
(Selector_Name
(P
))) /= E_Component
1592 Ekind
(Entity
(Selector_Name
(P
))) /= E_Discriminant
)
1594 Error_Attr_P
("prefix for % attribute must be selected component");
1596 end Check_Component
;
1598 ------------------------------------
1599 -- Check_Decimal_Fixed_Point_Type --
1600 ------------------------------------
1602 procedure Check_Decimal_Fixed_Point_Type
is
1606 if not Is_Decimal_Fixed_Point_Type
(P_Type
) then
1607 Error_Attr_P
("prefix of % attribute must be decimal type");
1609 end Check_Decimal_Fixed_Point_Type
;
1611 -----------------------
1612 -- Check_Dereference --
1613 -----------------------
1615 procedure Check_Dereference
is
1618 -- Case of a subtype mark
1620 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
1624 -- Case of an expression
1628 if Is_Access_Type
(P_Type
) then
1630 -- If there is an implicit dereference, then we must freeze the
1631 -- designated type of the access type, since the type of the
1632 -- referenced array is this type (see AI95-00106).
1634 -- As done elsewhere, freezing must not happen when pre-analyzing
1635 -- a pre- or postcondition or a default value for an object or for
1636 -- a formal parameter.
1638 if not In_Spec_Expression
then
1639 Freeze_Before
(N
, Designated_Type
(P_Type
));
1643 Make_Explicit_Dereference
(Sloc
(P
),
1644 Prefix
=> Relocate_Node
(P
)));
1646 Analyze_And_Resolve
(P
);
1647 P_Type
:= Etype
(P
);
1649 if P_Type
= Any_Type
then
1650 raise Bad_Attribute
;
1653 P_Base_Type
:= Base_Type
(P_Type
);
1655 end Check_Dereference
;
1657 -------------------------
1658 -- Check_Discrete_Type --
1659 -------------------------
1661 procedure Check_Discrete_Type
is
1665 if not Is_Discrete_Type
(P_Type
) then
1666 Error_Attr_P
("prefix of % attribute must be discrete type");
1668 end Check_Discrete_Type
;
1674 procedure Check_E0
is
1676 if Present
(E1
) then
1677 Unexpected_Argument
(E1
);
1685 procedure Check_E1
is
1687 Check_Either_E0_Or_E1
;
1691 -- Special-case attributes that are functions and that appear as
1692 -- the prefix of another attribute. Error is posted on parent.
1694 if Nkind
(Parent
(N
)) = N_Attribute_Reference
1695 and then Nam_In
(Attribute_Name
(Parent
(N
)), Name_Address
,
1699 Error_Msg_Name_1
:= Attribute_Name
(Parent
(N
));
1700 Error_Msg_N
("illegal prefix for % attribute", Parent
(N
));
1701 Set_Etype
(Parent
(N
), Any_Type
);
1702 Set_Entity
(Parent
(N
), Any_Type
);
1703 raise Bad_Attribute
;
1706 Error_Attr
("missing argument for % attribute", N
);
1715 procedure Check_E2
is
1718 Error_Attr
("missing arguments for % attribute (2 required)", N
);
1720 Error_Attr
("missing argument for % attribute (2 required)", N
);
1724 ---------------------------
1725 -- Check_Either_E0_Or_E1 --
1726 ---------------------------
1728 procedure Check_Either_E0_Or_E1
is
1730 if Present
(E2
) then
1731 Unexpected_Argument
(E2
);
1733 end Check_Either_E0_Or_E1
;
1735 ----------------------
1736 -- Check_Enum_Image --
1737 ----------------------
1739 procedure Check_Enum_Image
is
1743 -- When an enumeration type appears in an attribute reference, all
1744 -- literals of the type are marked as referenced. This must only be
1745 -- done if the attribute reference appears in the current source.
1746 -- Otherwise the information on references may differ between a
1747 -- normal compilation and one that performs inlining.
1749 if Is_Enumeration_Type
(P_Base_Type
)
1750 and then In_Extended_Main_Code_Unit
(N
)
1752 Lit
:= First_Literal
(P_Base_Type
);
1753 while Present
(Lit
) loop
1754 Set_Referenced
(Lit
);
1758 end Check_Enum_Image
;
1760 ----------------------------
1761 -- Check_First_Last_Valid --
1762 ----------------------------
1764 procedure Check_First_Last_Valid
is
1766 Check_Discrete_Type
;
1768 -- Freeze the subtype now, so that the following test for predicates
1769 -- works (we set the predicates stuff up at freeze time)
1771 Insert_Actions
(N
, Freeze_Entity
(P_Type
, P
));
1773 -- Now test for dynamic predicate
1775 if Has_Predicates
(P_Type
)
1776 and then not (Has_Static_Predicate
(P_Type
))
1779 ("prefix of % attribute may not have dynamic predicate");
1782 -- Check non-static subtype
1784 if not Is_OK_Static_Subtype
(P_Type
) then
1785 Error_Attr_P
("prefix of % attribute must be a static subtype");
1788 -- Test case for no values
1790 if Expr_Value
(Type_Low_Bound
(P_Type
)) >
1791 Expr_Value
(Type_High_Bound
(P_Type
))
1792 or else (Has_Predicates
(P_Type
)
1794 Is_Empty_List
(Static_Discrete_Predicate
(P_Type
)))
1797 ("prefix of % attribute must be subtype with at least one "
1800 end Check_First_Last_Valid
;
1802 ----------------------------
1803 -- Check_Fixed_Point_Type --
1804 ----------------------------
1806 procedure Check_Fixed_Point_Type
is
1810 if not Is_Fixed_Point_Type
(P_Type
) then
1811 Error_Attr_P
("prefix of % attribute must be fixed point type");
1813 end Check_Fixed_Point_Type
;
1815 ------------------------------
1816 -- Check_Fixed_Point_Type_0 --
1817 ------------------------------
1819 procedure Check_Fixed_Point_Type_0
is
1821 Check_Fixed_Point_Type
;
1823 end Check_Fixed_Point_Type_0
;
1825 -------------------------------
1826 -- Check_Floating_Point_Type --
1827 -------------------------------
1829 procedure Check_Floating_Point_Type
is
1833 if not Is_Floating_Point_Type
(P_Type
) then
1834 Error_Attr_P
("prefix of % attribute must be float type");
1836 end Check_Floating_Point_Type
;
1838 ---------------------------------
1839 -- Check_Floating_Point_Type_0 --
1840 ---------------------------------
1842 procedure Check_Floating_Point_Type_0
is
1844 Check_Floating_Point_Type
;
1846 end Check_Floating_Point_Type_0
;
1848 ---------------------------------
1849 -- Check_Floating_Point_Type_1 --
1850 ---------------------------------
1852 procedure Check_Floating_Point_Type_1
is
1854 Check_Floating_Point_Type
;
1856 end Check_Floating_Point_Type_1
;
1858 ---------------------------------
1859 -- Check_Floating_Point_Type_2 --
1860 ---------------------------------
1862 procedure Check_Floating_Point_Type_2
is
1864 Check_Floating_Point_Type
;
1866 end Check_Floating_Point_Type_2
;
1868 ------------------------
1869 -- Check_Integer_Type --
1870 ------------------------
1872 procedure Check_Integer_Type
is
1876 if not Is_Integer_Type
(P_Type
) then
1877 Error_Attr_P
("prefix of % attribute must be integer type");
1879 end Check_Integer_Type
;
1881 --------------------------------
1882 -- Check_Modular_Integer_Type --
1883 --------------------------------
1885 procedure Check_Modular_Integer_Type
is
1889 if not Is_Modular_Integer_Type
(P_Type
) then
1891 ("prefix of % attribute must be modular integer type");
1893 end Check_Modular_Integer_Type
;
1895 ------------------------
1896 -- Check_Not_CPP_Type --
1897 ------------------------
1899 procedure Check_Not_CPP_Type
is
1901 if Is_Tagged_Type
(Etype
(P
))
1902 and then Convention
(Etype
(P
)) = Convention_CPP
1903 and then Is_CPP_Class
(Root_Type
(Etype
(P
)))
1906 ("invalid use of % attribute with 'C'P'P tagged type");
1908 end Check_Not_CPP_Type
;
1910 -------------------------------
1911 -- Check_Not_Incomplete_Type --
1912 -------------------------------
1914 procedure Check_Not_Incomplete_Type
is
1919 -- Ada 2005 (AI-50217, AI-326): If the prefix is an explicit
1920 -- dereference we have to check wrong uses of incomplete types
1921 -- (other wrong uses are checked at their freezing point).
1923 -- In Ada 2012, incomplete types can appear in subprogram
1924 -- profiles, but formals with incomplete types cannot be the
1925 -- prefix of attributes.
1927 -- Example 1: Limited-with
1929 -- limited with Pkg;
1931 -- type Acc is access Pkg.T;
1933 -- S : Integer := X.all'Size; -- ERROR
1936 -- Example 2: Tagged incomplete
1938 -- type T is tagged;
1939 -- type Acc is access all T;
1941 -- S : constant Integer := X.all'Size; -- ERROR
1942 -- procedure Q (Obj : Integer := X.all'Alignment); -- ERROR
1944 if Ada_Version
>= Ada_2005
1945 and then Nkind
(P
) = N_Explicit_Dereference
1948 while Nkind
(E
) = N_Explicit_Dereference
loop
1954 if From_Limited_With
(Typ
) then
1956 ("prefix of % attribute cannot be an incomplete type");
1958 -- If the prefix is an access type check the designated type
1960 elsif Is_Access_Type
(Typ
)
1961 and then Nkind
(P
) = N_Explicit_Dereference
1963 Typ
:= Directly_Designated_Type
(Typ
);
1966 if Is_Class_Wide_Type
(Typ
) then
1967 Typ
:= Root_Type
(Typ
);
1970 -- A legal use of a shadow entity occurs only when the unit where
1971 -- the non-limited view resides is imported via a regular with
1972 -- clause in the current body. Such references to shadow entities
1973 -- may occur in subprogram formals.
1975 if Is_Incomplete_Type
(Typ
)
1976 and then From_Limited_With
(Typ
)
1977 and then Present
(Non_Limited_View
(Typ
))
1978 and then Is_Legal_Shadow_Entity_In_Body
(Typ
)
1980 Typ
:= Non_Limited_View
(Typ
);
1983 -- If still incomplete, it can be a local incomplete type, or a
1984 -- limited view whose scope is also a limited view.
1986 if Ekind
(Typ
) = E_Incomplete_Type
then
1987 if not From_Limited_With
(Typ
)
1988 and then No
(Full_View
(Typ
))
1991 ("prefix of % attribute cannot be an incomplete type");
1993 -- The limited view may be available indirectly through
1994 -- an intermediate unit. If the non-limited view is available
1995 -- the attribute reference is legal.
1997 elsif From_Limited_With
(Typ
)
1999 (No
(Non_Limited_View
(Typ
))
2000 or else Is_Incomplete_Type
(Non_Limited_View
(Typ
)))
2003 ("prefix of % attribute cannot be an incomplete type");
2007 -- Ada 2012 : formals in bodies may be incomplete, but no attribute
2010 elsif Is_Entity_Name
(P
)
2011 and then Is_Formal
(Entity
(P
))
2012 and then Is_Incomplete_Type
(Etype
(Etype
(P
)))
2015 ("prefix of % attribute cannot be an incomplete type");
2018 if not Is_Entity_Name
(P
)
2019 or else not Is_Type
(Entity
(P
))
2020 or else In_Spec_Expression
2024 Check_Fully_Declared
(P_Type
, P
);
2026 end Check_Not_Incomplete_Type
;
2028 ----------------------------
2029 -- Check_Object_Reference --
2030 ----------------------------
2032 procedure Check_Object_Reference
(P
: Node_Id
) is
2036 -- If we need an object, and we have a prefix that is the name of
2037 -- a function entity, convert it into a function call.
2039 if Is_Entity_Name
(P
)
2040 and then Ekind
(Entity
(P
)) = E_Function
2042 Rtyp
:= Etype
(Entity
(P
));
2045 Make_Function_Call
(Sloc
(P
),
2046 Name
=> Relocate_Node
(P
)));
2048 Analyze_And_Resolve
(P
, Rtyp
);
2050 -- Otherwise we must have an object reference
2052 elsif not Is_Object_Reference
(P
) then
2053 Error_Attr_P
("prefix of % attribute must be object");
2055 end Check_Object_Reference
;
2057 ----------------------------
2058 -- Check_PolyORB_Attribute --
2059 ----------------------------
2061 procedure Check_PolyORB_Attribute
is
2063 Validate_Non_Static_Attribute_Function_Call
;
2068 if Get_PCS_Name
/= Name_PolyORB_DSA
then
2070 ("attribute% requires the 'Poly'O'R'B 'P'C'S", N
);
2072 end Check_PolyORB_Attribute
;
2074 ------------------------
2075 -- Check_Program_Unit --
2076 ------------------------
2078 procedure Check_Program_Unit
is
2080 if Is_Entity_Name
(P
) then
2082 K
: constant Entity_Kind
:= Ekind
(Entity
(P
));
2083 T
: constant Entity_Id
:= Etype
(Entity
(P
));
2086 if K
in Subprogram_Kind
2087 or else K
in Task_Kind
2088 or else K
in Protected_Kind
2089 or else K
= E_Package
2090 or else K
in Generic_Unit_Kind
2091 or else (K
= E_Variable
2095 Is_Protected_Type
(T
)))
2102 Error_Attr_P
("prefix of % attribute must be program unit");
2103 end Check_Program_Unit
;
2105 ---------------------
2106 -- Check_Real_Type --
2107 ---------------------
2109 procedure Check_Real_Type
is
2113 if not Is_Real_Type
(P_Type
) then
2114 Error_Attr_P
("prefix of % attribute must be real type");
2116 end Check_Real_Type
;
2118 -----------------------
2119 -- Check_Scalar_Type --
2120 -----------------------
2122 procedure Check_Scalar_Type
is
2126 if not Is_Scalar_Type
(P_Type
) then
2127 Error_Attr_P
("prefix of % attribute must be scalar type");
2129 end Check_Scalar_Type
;
2131 ------------------------------------------
2132 -- Check_SPARK_05_Restriction_On_Attribute --
2133 ------------------------------------------
2135 procedure Check_SPARK_05_Restriction_On_Attribute
is
2137 Error_Msg_Name_1
:= Aname
;
2138 Check_SPARK_05_Restriction
("attribute % is not allowed", P
);
2139 end Check_SPARK_05_Restriction_On_Attribute
;
2141 ---------------------------
2142 -- Check_Standard_Prefix --
2143 ---------------------------
2145 procedure Check_Standard_Prefix
is
2149 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_Standard
then
2150 Error_Attr
("only allowed prefix for % attribute is Standard", P
);
2152 end Check_Standard_Prefix
;
2154 ----------------------------
2155 -- Check_Stream_Attribute --
2156 ----------------------------
2158 procedure Check_Stream_Attribute
(Nam
: TSS_Name_Type
) is
2162 In_Shared_Var_Procs
: Boolean;
2163 -- True when compiling System.Shared_Storage.Shared_Var_Procs body.
2164 -- For this runtime package (always compiled in GNAT mode), we allow
2165 -- stream attributes references for limited types for the case where
2166 -- shared passive objects are implemented using stream attributes,
2167 -- which is the default in GNAT's persistent storage implementation.
2170 Validate_Non_Static_Attribute_Function_Call
;
2172 -- With the exception of 'Input, Stream attributes are procedures,
2173 -- and can only appear at the position of procedure calls. We check
2174 -- for this here, before they are rewritten, to give a more precise
2177 if Nam
= TSS_Stream_Input
then
2180 elsif Is_List_Member
(N
)
2181 and then not Nkind_In
(Parent
(N
), N_Procedure_Call_Statement
,
2188 ("invalid context for attribute%, which is a procedure", N
);
2192 Btyp
:= Implementation_Base_Type
(P_Type
);
2194 -- Stream attributes not allowed on limited types unless the
2195 -- attribute reference was generated by the expander (in which
2196 -- case the underlying type will be used, as described in Sinfo),
2197 -- or the attribute was specified explicitly for the type itself
2198 -- or one of its ancestors (taking visibility rules into account if
2199 -- in Ada 2005 mode), or a pragma Stream_Convert applies to Btyp
2200 -- (with no visibility restriction).
2203 Gen_Body
: constant Node_Id
:= Enclosing_Generic_Body
(N
);
2205 if Present
(Gen_Body
) then
2206 In_Shared_Var_Procs
:=
2207 Is_RTE
(Corresponding_Spec
(Gen_Body
), RE_Shared_Var_Procs
);
2209 In_Shared_Var_Procs
:= False;
2213 if (Comes_From_Source
(N
)
2214 and then not (In_Shared_Var_Procs
or In_Instance
))
2215 and then not Stream_Attribute_Available
(P_Type
, Nam
)
2216 and then not Has_Rep_Pragma
(Btyp
, Name_Stream_Convert
)
2218 Error_Msg_Name_1
:= Aname
;
2220 if Is_Limited_Type
(P_Type
) then
2222 ("limited type& has no% attribute", P
, P_Type
);
2223 Explain_Limited_Type
(P_Type
, P
);
2226 ("attribute% for type& is not available", P
, P_Type
);
2230 -- Check for no stream operations allowed from No_Tagged_Streams
2232 if Is_Tagged_Type
(P_Type
)
2233 and then Present
(No_Tagged_Streams_Pragma
(P_Type
))
2235 Error_Msg_Sloc
:= Sloc
(No_Tagged_Streams_Pragma
(P_Type
));
2237 ("no stream operations for & (No_Tagged_Streams #)", N
, P_Type
);
2241 -- Check restriction violations
2243 -- First check the No_Streams restriction, which prohibits the use
2244 -- of explicit stream attributes in the source program. We do not
2245 -- prevent the occurrence of stream attributes in generated code,
2246 -- for instance those generated implicitly for dispatching purposes.
2248 if Comes_From_Source
(N
) then
2249 Check_Restriction
(No_Streams
, P
);
2252 -- AI05-0057: if restriction No_Default_Stream_Attributes is active,
2253 -- it is illegal to use a predefined elementary type stream attribute
2254 -- either by itself, or more importantly as part of the attribute
2255 -- subprogram for a composite type. However, if the broader
2256 -- restriction No_Streams is active, stream operations are not
2257 -- generated, and there is no error.
2259 if Restriction_Active
(No_Default_Stream_Attributes
)
2260 and then not Restriction_Active
(No_Streams
)
2266 if Nam
= TSS_Stream_Input
2268 Nam
= TSS_Stream_Read
2271 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Read
);
2274 Type_Without_Stream_Operation
(P_Type
, TSS_Stream_Write
);
2278 Check_Restriction
(No_Default_Stream_Attributes
, N
);
2281 ("missing user-defined Stream Read or Write for type&",
2283 if not Is_Elementary_Type
(P_Type
) then
2285 ("\which is a component of type&", N
, P_Type
);
2291 -- Check special case of Exception_Id and Exception_Occurrence which
2292 -- are not allowed for restriction No_Exception_Registration.
2294 if Restriction_Check_Required
(No_Exception_Registration
)
2295 and then (Is_RTE
(P_Type
, RE_Exception_Id
)
2297 Is_RTE
(P_Type
, RE_Exception_Occurrence
))
2299 Check_Restriction
(No_Exception_Registration
, P
);
2302 -- Here we must check that the first argument is an access type
2303 -- that is compatible with Ada.Streams.Root_Stream_Type'Class.
2305 Analyze_And_Resolve
(E1
);
2308 -- Note: the double call to Root_Type here is needed because the
2309 -- root type of a class-wide type is the corresponding type (e.g.
2310 -- X for X'Class, and we really want to go to the root.)
2312 if not Is_Access_Type
(Etyp
)
2313 or else Root_Type
(Root_Type
(Designated_Type
(Etyp
))) /=
2314 RTE
(RE_Root_Stream_Type
)
2317 ("expected access to Ada.Streams.Root_Stream_Type''Class", E1
);
2320 -- Check that the second argument is of the right type if there is
2321 -- one (the Input attribute has only one argument so this is skipped)
2323 if Present
(E2
) then
2326 if Nam
= TSS_Stream_Read
2327 and then not Is_OK_Variable_For_Out_Formal
(E2
)
2330 ("second argument of % attribute must be a variable", E2
);
2333 Resolve
(E2
, P_Type
);
2337 end Check_Stream_Attribute
;
2339 -------------------------
2340 -- Check_System_Prefix --
2341 -------------------------
2343 procedure Check_System_Prefix
is
2345 if Nkind
(P
) /= N_Identifier
or else Chars
(P
) /= Name_System
then
2346 Error_Attr
("only allowed prefix for % attribute is System", P
);
2348 end Check_System_Prefix
;
2350 -----------------------
2351 -- Check_Task_Prefix --
2352 -----------------------
2354 procedure Check_Task_Prefix
is
2358 -- Ada 2005 (AI-345): Attribute 'Terminated can be applied to
2359 -- task interface class-wide types.
2361 if Is_Task_Type
(Etype
(P
))
2362 or else (Is_Access_Type
(Etype
(P
))
2363 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
2364 or else (Ada_Version
>= Ada_2005
2365 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
2366 and then Is_Interface
(Etype
(P
))
2367 and then Is_Task_Interface
(Etype
(P
)))
2372 if Ada_Version
>= Ada_2005
then
2374 ("prefix of % attribute must be a task or a task " &
2375 "interface class-wide object");
2378 Error_Attr_P
("prefix of % attribute must be a task");
2381 end Check_Task_Prefix
;
2387 -- The possibilities are an entity name denoting a type, or an
2388 -- attribute reference that denotes a type (Base or Class). If
2389 -- the type is incomplete, replace it with its full view.
2391 procedure Check_Type
is
2393 if not Is_Entity_Name
(P
)
2394 or else not Is_Type
(Entity
(P
))
2396 Error_Attr_P
("prefix of % attribute must be a type");
2398 elsif Is_Protected_Self_Reference
(P
) then
2400 ("prefix of % attribute denotes current instance "
2401 & "(RM 9.4(21/2))");
2403 elsif Ekind
(Entity
(P
)) = E_Incomplete_Type
2404 and then Present
(Full_View
(Entity
(P
)))
2406 P_Type
:= Full_View
(Entity
(P
));
2407 Set_Entity
(P
, P_Type
);
2411 ---------------------
2412 -- Check_Unit_Name --
2413 ---------------------
2415 procedure Check_Unit_Name
(Nod
: Node_Id
) is
2417 if Nkind
(Nod
) = N_Identifier
then
2420 elsif Nkind_In
(Nod
, N_Selected_Component
, N_Expanded_Name
) then
2421 Check_Unit_Name
(Prefix
(Nod
));
2423 if Nkind
(Selector_Name
(Nod
)) = N_Identifier
then
2428 Error_Attr
("argument for % attribute must be unit name", P
);
2429 end Check_Unit_Name
;
2435 procedure Error_Attr
is
2437 Set_Etype
(N
, Any_Type
);
2438 Set_Entity
(N
, Any_Type
);
2439 raise Bad_Attribute
;
2442 procedure Error_Attr
(Msg
: String; Error_Node
: Node_Id
) is
2444 Error_Msg_Name_1
:= Aname
;
2445 Error_Msg_N
(Msg
, Error_Node
);
2453 procedure Error_Attr_P
(Msg
: String) is
2455 Error_Msg_Name_1
:= Aname
;
2456 Error_Msg_F
(Msg
, P
);
2460 ----------------------------
2461 -- Legal_Formal_Attribute --
2462 ----------------------------
2464 procedure Legal_Formal_Attribute
is
2468 if not Is_Entity_Name
(P
)
2469 or else not Is_Type
(Entity
(P
))
2471 Error_Attr_P
("prefix of % attribute must be generic type");
2473 elsif Is_Generic_Actual_Type
(Entity
(P
))
2475 or else In_Inlined_Body
2479 elsif Is_Generic_Type
(Entity
(P
)) then
2480 if Is_Definite_Subtype
(Entity
(P
)) then
2482 ("prefix of % attribute must be indefinite generic type");
2487 ("prefix of % attribute must be indefinite generic type");
2490 Set_Etype
(N
, Standard_Boolean
);
2491 end Legal_Formal_Attribute
;
2493 ---------------------------------------------------------------
2494 -- Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements --
2495 ---------------------------------------------------------------
2497 procedure Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
is
2501 Check_Not_Incomplete_Type
;
2502 Set_Etype
(N
, Universal_Integer
);
2503 end Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
2509 procedure Min_Max
is
2513 Resolve
(E1
, P_Base_Type
);
2514 Resolve
(E2
, P_Base_Type
);
2515 Set_Etype
(N
, P_Base_Type
);
2517 -- Check for comparison on unordered enumeration type
2519 if Bad_Unordered_Enumeration_Reference
(N
, P_Base_Type
) then
2520 Error_Msg_Sloc
:= Sloc
(P_Base_Type
);
2522 ("comparison on unordered enumeration type& declared#?U?",
2527 ------------------------
2528 -- Standard_Attribute --
2529 ------------------------
2531 procedure Standard_Attribute
(Val
: Int
) is
2533 Check_Standard_Prefix
;
2534 Rewrite
(N
, Make_Integer_Literal
(Loc
, Val
));
2536 Set_Is_Static_Expression
(N
, True);
2537 end Standard_Attribute
;
2539 --------------------
2540 -- Uneval_Old_Msg --
2541 --------------------
2543 procedure Uneval_Old_Msg
is
2544 Uneval_Old_Setting
: Character;
2548 -- If from aspect, then Uneval_Old_Setting comes from flags in the
2549 -- N_Aspect_Specification node that corresponds to the attribute.
2551 -- First find the pragma in which we appear (note that at this stage,
2552 -- even if we appeared originally within an aspect specification, we
2553 -- are now within the corresponding pragma).
2557 Prag
:= Parent
(Prag
);
2558 exit when No
(Prag
) or else Nkind
(Prag
) = N_Pragma
;
2561 if Present
(Prag
) then
2562 if Uneval_Old_Accept
(Prag
) then
2563 Uneval_Old_Setting
:= 'A';
2564 elsif Uneval_Old_Warn
(Prag
) then
2565 Uneval_Old_Setting
:= 'W';
2567 Uneval_Old_Setting
:= 'E';
2570 -- If we did not find the pragma, that's odd, just use the setting
2571 -- from Opt.Uneval_Old. Perhaps this is due to a previous error?
2574 Uneval_Old_Setting
:= Opt
.Uneval_Old
;
2577 -- Processing depends on the setting of Uneval_Old
2579 case Uneval_Old_Setting
is
2582 ("prefix of attribute % that is potentially "
2583 & "unevaluated must denote an entity");
2586 Error_Msg_Name_1
:= Aname
;
2588 ("??prefix of attribute % appears in potentially "
2589 & "unevaluated context, exception may be raised", P
);
2595 raise Program_Error
;
2599 -------------------------
2600 -- Unexpected Argument --
2601 -------------------------
2603 procedure Unexpected_Argument
(En
: Node_Id
) is
2605 Error_Attr
("unexpected argument for % attribute", En
);
2606 end Unexpected_Argument
;
2608 -------------------------------------------------
2609 -- Validate_Non_Static_Attribute_Function_Call --
2610 -------------------------------------------------
2612 -- This function should be moved to Sem_Dist ???
2614 procedure Validate_Non_Static_Attribute_Function_Call
is
2616 if In_Preelaborated_Unit
2617 and then not In_Subprogram_Or_Concurrent_Unit
2619 Flag_Non_Static_Expr
2620 ("non-static function call in preelaborated unit!", N
);
2622 end Validate_Non_Static_Attribute_Function_Call
;
2624 -- Start of processing for Analyze_Attribute
2627 -- Immediate return if unrecognized attribute (already diagnosed
2628 -- by parser, so there is nothing more that we need to do)
2630 if not Is_Attribute_Name
(Aname
) then
2631 raise Bad_Attribute
;
2634 -- Deal with Ada 83 issues
2636 if Comes_From_Source
(N
) then
2637 if not Attribute_83
(Attr_Id
) then
2638 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
2639 Error_Msg_Name_1
:= Aname
;
2640 Error_Msg_N
("(Ada 83) attribute% is not standard??", N
);
2643 if Attribute_Impl_Def
(Attr_Id
) then
2644 Check_Restriction
(No_Implementation_Attributes
, N
);
2649 -- Deal with Ada 2005 attributes that are implementation attributes
2650 -- because they appear in a version of Ada before Ada 2005, and
2651 -- similarly for Ada 2012 attributes appearing in an earlier version.
2653 if (Attribute_05
(Attr_Id
) and then Ada_Version
< Ada_2005
)
2655 (Attribute_12
(Attr_Id
) and then Ada_Version
< Ada_2012
)
2657 Check_Restriction
(No_Implementation_Attributes
, N
);
2660 -- Remote access to subprogram type access attribute reference needs
2661 -- unanalyzed copy for tree transformation. The analyzed copy is used
2662 -- for its semantic information (whether prefix is a remote subprogram
2663 -- name), the unanalyzed copy is used to construct new subtree rooted
2664 -- with N_Aggregate which represents a fat pointer aggregate.
2666 if Aname
= Name_Access
then
2667 Discard_Node
(Copy_Separate_Tree
(N
));
2670 -- Analyze prefix and exit if error in analysis. If the prefix is an
2671 -- incomplete type, use full view if available. Note that there are
2672 -- some attributes for which we do not analyze the prefix, since the
2673 -- prefix is not a normal name, or else needs special handling.
2675 if Aname
/= Name_Elab_Body
and then
2676 Aname
/= Name_Elab_Spec
and then
2677 Aname
/= Name_Elab_Subp_Body
and then
2678 Aname
/= Name_Enabled
and then
2682 P_Type
:= Etype
(P
);
2684 if Is_Entity_Name
(P
)
2685 and then Present
(Entity
(P
))
2686 and then Is_Type
(Entity
(P
))
2688 if Ekind
(Entity
(P
)) = E_Incomplete_Type
then
2689 P_Type
:= Get_Full_View
(P_Type
);
2690 Set_Entity
(P
, P_Type
);
2691 Set_Etype
(P
, P_Type
);
2693 elsif Entity
(P
) = Current_Scope
2694 and then Is_Record_Type
(Entity
(P
))
2696 -- Use of current instance within the type. Verify that if the
2697 -- attribute appears within a constraint, it yields an access
2698 -- type, other uses are illegal.
2706 and then Nkind
(Parent
(Par
)) /= N_Component_Definition
2708 Par
:= Parent
(Par
);
2712 and then Nkind
(Par
) = N_Subtype_Indication
2714 if Attr_Id
/= Attribute_Access
2715 and then Attr_Id
/= Attribute_Unchecked_Access
2716 and then Attr_Id
/= Attribute_Unrestricted_Access
2719 ("in a constraint the current instance can only "
2720 & "be used with an access attribute", N
);
2727 if P_Type
= Any_Type
then
2728 raise Bad_Attribute
;
2731 P_Base_Type
:= Base_Type
(P_Type
);
2734 -- Analyze expressions that may be present, exiting if an error occurs
2741 E1
:= First
(Exprs
);
2743 -- Skip analysis for case of Restriction_Set, we do not expect
2744 -- the argument to be analyzed in this case.
2746 if Aname
/= Name_Restriction_Set
then
2749 -- Check for missing/bad expression (result of previous error)
2751 if No
(E1
) or else Etype
(E1
) = Any_Type
then
2752 raise Bad_Attribute
;
2758 if Present
(E2
) then
2761 if Etype
(E2
) = Any_Type
then
2762 raise Bad_Attribute
;
2765 if Present
(Next
(E2
)) then
2766 Unexpected_Argument
(Next
(E2
));
2771 -- Cases where prefix must be resolvable by itself
2773 if Is_Overloaded
(P
)
2774 and then Aname
/= Name_Access
2775 and then Aname
/= Name_Address
2776 and then Aname
/= Name_Code_Address
2777 and then Aname
/= Name_Result
2778 and then Aname
/= Name_Unchecked_Access
2780 -- The prefix must be resolvable by itself, without reference to the
2781 -- attribute. One case that requires special handling is a prefix
2782 -- that is a function name, where one interpretation may be a
2783 -- parameterless call. Entry attributes are handled specially below.
2785 if Is_Entity_Name
(P
)
2786 and then not Nam_In
(Aname
, Name_Count
, Name_Caller
)
2788 Check_Parameterless_Call
(P
);
2791 if Is_Overloaded
(P
) then
2793 -- Ada 2005 (AI-345): Since protected and task types have
2794 -- primitive entry wrappers, the attributes Count, and Caller
2795 -- require a context check
2797 if Nam_In
(Aname
, Name_Count
, Name_Caller
) then
2799 Count
: Natural := 0;
2804 Get_First_Interp
(P
, I
, It
);
2805 while Present
(It
.Nam
) loop
2806 if Comes_From_Source
(It
.Nam
) then
2812 Get_Next_Interp
(I
, It
);
2816 Error_Attr
("ambiguous prefix for % attribute", P
);
2818 Set_Is_Overloaded
(P
, False);
2823 Error_Attr
("ambiguous prefix for % attribute", P
);
2828 -- In SPARK, attributes of private types are only allowed if the full
2829 -- type declaration is visible.
2831 -- Note: the check for Present (Entity (P)) defends against some error
2832 -- conditions where the Entity field is not set.
2834 if Is_Entity_Name
(P
) and then Present
(Entity
(P
))
2835 and then Is_Type
(Entity
(P
))
2836 and then Is_Private_Type
(P_Type
)
2837 and then not In_Open_Scopes
(Scope
(P_Type
))
2838 and then not In_Spec_Expression
2840 Check_SPARK_05_Restriction
("invisible attribute of type", N
);
2843 -- Remaining processing depends on attribute
2847 -- Attributes related to Ada 2012 iterators. Attribute specifications
2848 -- exist for these, but they cannot be queried.
2850 when Attribute_Constant_Indexing |
2851 Attribute_Default_Iterator |
2852 Attribute_Implicit_Dereference |
2853 Attribute_Iterator_Element |
2854 Attribute_Iterable |
2855 Attribute_Variable_Indexing
=>
2856 Error_Msg_N
("illegal attribute", N
);
2858 -- Internal attributes used to deal with Ada 2012 delayed aspects. These
2859 -- were already rejected by the parser. Thus they shouldn't appear here.
2861 when Internal_Attribute_Id
=>
2862 raise Program_Error
;
2868 when Attribute_Abort_Signal
=>
2869 Check_Standard_Prefix
;
2870 Rewrite
(N
, New_Occurrence_Of
(Stand
.Abort_Signal
, Loc
));
2877 when Attribute_Access
=>
2878 Analyze_Access_Attribute
;
2879 Check_Not_Incomplete_Type
;
2885 when Attribute_Address
=>
2888 Check_Not_Incomplete_Type
;
2889 Set_Etype
(N
, RTE
(RE_Address
));
2895 when Attribute_Address_Size
=>
2896 Standard_Attribute
(System_Address_Size
);
2902 when Attribute_Adjacent
=>
2903 Check_Floating_Point_Type_2
;
2904 Set_Etype
(N
, P_Base_Type
);
2905 Resolve
(E1
, P_Base_Type
);
2906 Resolve
(E2
, P_Base_Type
);
2912 when Attribute_Aft
=>
2913 Check_Fixed_Point_Type_0
;
2914 Set_Etype
(N
, Universal_Integer
);
2920 when Attribute_Alignment
=>
2922 -- Don't we need more checking here, cf Size ???
2925 Check_Not_Incomplete_Type
;
2927 Set_Etype
(N
, Universal_Integer
);
2933 when Attribute_Asm_Input
=>
2934 Check_Asm_Attribute
;
2936 -- The back-end may need to take the address of E2
2938 if Is_Entity_Name
(E2
) then
2939 Set_Address_Taken
(Entity
(E2
));
2942 Set_Etype
(N
, RTE
(RE_Asm_Input_Operand
));
2948 when Attribute_Asm_Output
=>
2949 Check_Asm_Attribute
;
2951 if Etype
(E2
) = Any_Type
then
2954 elsif Aname
= Name_Asm_Output
then
2955 if not Is_Variable
(E2
) then
2957 ("second argument for Asm_Output is not variable", E2
);
2961 Note_Possible_Modification
(E2
, Sure
=> True);
2963 -- The back-end may need to take the address of E2
2965 if Is_Entity_Name
(E2
) then
2966 Set_Address_Taken
(Entity
(E2
));
2969 Set_Etype
(N
, RTE
(RE_Asm_Output_Operand
));
2971 -----------------------------
2972 -- Atomic_Always_Lock_Free --
2973 -----------------------------
2975 when Attribute_Atomic_Always_Lock_Free
=>
2978 Set_Etype
(N
, Standard_Boolean
);
2984 -- Note: when the base attribute appears in the context of a subtype
2985 -- mark, the analysis is done by Sem_Ch8.Find_Type, rather than by
2986 -- the following circuit.
2988 when Attribute_Base
=> Base
: declare
2996 if Ada_Version
>= Ada_95
2997 and then not Is_Scalar_Type
(Typ
)
2998 and then not Is_Generic_Type
(Typ
)
3000 Error_Attr_P
("prefix of Base attribute must be scalar type");
3002 elsif Sloc
(Typ
) = Standard_Location
3003 and then Base_Type
(Typ
) = Typ
3004 and then Warn_On_Redundant_Constructs
3006 Error_Msg_NE
-- CODEFIX
3007 ("?r?redundant attribute, & is its own base type", N
, Typ
);
3010 if Nkind
(Parent
(N
)) /= N_Attribute_Reference
then
3011 Error_Msg_Name_1
:= Aname
;
3012 Check_SPARK_05_Restriction
3013 ("attribute% is only allowed as prefix of another attribute", P
);
3016 Set_Etype
(N
, Base_Type
(Entity
(P
)));
3017 Set_Entity
(N
, Base_Type
(Entity
(P
)));
3018 Rewrite
(N
, New_Occurrence_Of
(Entity
(N
), Loc
));
3026 when Attribute_Bit
=> Bit
:
3030 if not Is_Object_Reference
(P
) then
3031 Error_Attr_P
("prefix for % attribute must be object");
3033 -- What about the access object cases ???
3039 Set_Etype
(N
, Universal_Integer
);
3046 when Attribute_Bit_Order
=> Bit_Order
:
3051 if not Is_Record_Type
(P_Type
) then
3052 Error_Attr_P
("prefix of % attribute must be record type");
3055 if Bytes_Big_Endian
xor Reverse_Bit_Order
(P_Type
) then
3057 New_Occurrence_Of
(RTE
(RE_High_Order_First
), Loc
));
3060 New_Occurrence_Of
(RTE
(RE_Low_Order_First
), Loc
));
3063 Set_Etype
(N
, RTE
(RE_Bit_Order
));
3066 -- Reset incorrect indication of staticness
3068 Set_Is_Static_Expression
(N
, False);
3075 -- Note: in generated code, we can have a Bit_Position attribute
3076 -- applied to a (naked) record component (i.e. the prefix is an
3077 -- identifier that references an E_Component or E_Discriminant
3078 -- entity directly, and this is interpreted as expected by Gigi.
3079 -- The following code will not tolerate such usage, but when the
3080 -- expander creates this special case, it marks it as analyzed
3081 -- immediately and sets an appropriate type.
3083 when Attribute_Bit_Position
=>
3084 if Comes_From_Source
(N
) then
3088 Set_Etype
(N
, Universal_Integer
);
3094 when Attribute_Body_Version
=>
3097 Set_Etype
(N
, RTE
(RE_Version_String
));
3103 when Attribute_Callable
=>
3105 Set_Etype
(N
, Standard_Boolean
);
3112 when Attribute_Caller
=> Caller
: declare
3119 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3122 if not Is_Entry
(Ent
) then
3123 Error_Attr
("invalid entry name", N
);
3127 Error_Attr
("invalid entry name", N
);
3131 for J
in reverse 0 .. Scope_Stack
.Last
loop
3132 S
:= Scope_Stack
.Table
(J
).Entity
;
3134 if S
= Scope
(Ent
) then
3135 Error_Attr
("Caller must appear in matching accept or body", N
);
3141 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3148 when Attribute_Ceiling
=>
3149 Check_Floating_Point_Type_1
;
3150 Set_Etype
(N
, P_Base_Type
);
3151 Resolve
(E1
, P_Base_Type
);
3157 when Attribute_Class
=>
3158 Check_Restriction
(No_Dispatch
, N
);
3162 -- Applying Class to untagged incomplete type is obsolescent in Ada
3163 -- 2005. Note that we can't test Is_Tagged_Type here on P_Type, since
3164 -- this flag gets set by Find_Type in this situation.
3166 if Restriction_Check_Required
(No_Obsolescent_Features
)
3167 and then Ada_Version
>= Ada_2005
3168 and then Ekind
(P_Type
) = E_Incomplete_Type
3171 DN
: constant Node_Id
:= Declaration_Node
(P_Type
);
3173 if Nkind
(DN
) = N_Incomplete_Type_Declaration
3174 and then not Tagged_Present
(DN
)
3176 Check_Restriction
(No_Obsolescent_Features
, P
);
3185 when Attribute_Code_Address
=>
3188 if Nkind
(P
) = N_Attribute_Reference
3189 and then Nam_In
(Attribute_Name
(P
), Name_Elab_Body
, Name_Elab_Spec
)
3193 elsif not Is_Entity_Name
(P
)
3194 or else (Ekind
(Entity
(P
)) /= E_Function
3196 Ekind
(Entity
(P
)) /= E_Procedure
)
3198 Error_Attr
("invalid prefix for % attribute", P
);
3199 Set_Address_Taken
(Entity
(P
));
3201 -- Issue an error if the prefix denotes an eliminated subprogram
3204 Check_For_Eliminated_Subprogram
(P
, Entity
(P
));
3207 Set_Etype
(N
, RTE
(RE_Address
));
3209 ----------------------
3210 -- Compiler_Version --
3211 ----------------------
3213 when Attribute_Compiler_Version
=>
3215 Check_Standard_Prefix
;
3216 Rewrite
(N
, Make_String_Literal
(Loc
, "GNAT " & Gnat_Version_String
));
3217 Analyze_And_Resolve
(N
, Standard_String
);
3218 Set_Is_Static_Expression
(N
, True);
3220 --------------------
3221 -- Component_Size --
3222 --------------------
3224 when Attribute_Component_Size
=>
3226 Set_Etype
(N
, Universal_Integer
);
3228 -- Note: unlike other array attributes, unconstrained arrays are OK
3230 if Is_Array_Type
(P_Type
) and then not Is_Constrained
(P_Type
) then
3240 when Attribute_Compose
=>
3241 Check_Floating_Point_Type_2
;
3242 Set_Etype
(N
, P_Base_Type
);
3243 Resolve
(E1
, P_Base_Type
);
3244 Resolve
(E2
, Any_Integer
);
3250 when Attribute_Constrained
=>
3252 Set_Etype
(N
, Standard_Boolean
);
3254 -- Case from RM J.4(2) of constrained applied to private type
3256 if Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)) then
3257 Check_Restriction
(No_Obsolescent_Features
, P
);
3259 if Warn_On_Obsolescent_Feature
then
3261 ("constrained for private type is an " &
3262 "obsolescent feature (RM J.4)?j?", N
);
3265 -- If we are within an instance, the attribute must be legal
3266 -- because it was valid in the generic unit. Ditto if this is
3267 -- an inlining of a function declared in an instance.
3269 if In_Instance
or else In_Inlined_Body
then
3272 -- For sure OK if we have a real private type itself, but must
3273 -- be completed, cannot apply Constrained to incomplete type.
3275 elsif Is_Private_Type
(Entity
(P
)) then
3277 -- Note: this is one of the Annex J features that does not
3278 -- generate a warning from -gnatwj, since in fact it seems
3279 -- very useful, and is used in the GNAT runtime.
3281 Check_Not_Incomplete_Type
;
3285 -- Normal (non-obsolescent case) of application to object of
3286 -- a discriminated type.
3289 Check_Object_Reference
(P
);
3291 -- If N does not come from source, then we allow the
3292 -- the attribute prefix to be of a private type whose
3293 -- full type has discriminants. This occurs in cases
3294 -- involving expanded calls to stream attributes.
3296 if not Comes_From_Source
(N
) then
3297 P_Type
:= Underlying_Type
(P_Type
);
3300 -- Must have discriminants or be an access type designating
3301 -- a type with discriminants. If it is a classwide type it
3302 -- has unknown discriminants.
3304 if Has_Discriminants
(P_Type
)
3305 or else Has_Unknown_Discriminants
(P_Type
)
3307 (Is_Access_Type
(P_Type
)
3308 and then Has_Discriminants
(Designated_Type
(P_Type
)))
3312 -- The rule given in 3.7.2 is part of static semantics, but the
3313 -- intent is clearly that it be treated as a legality rule, and
3314 -- rechecked in the visible part of an instance. Nevertheless
3315 -- the intent also seems to be it should legally apply to the
3316 -- actual of a formal with unknown discriminants, regardless of
3317 -- whether the actual has discriminants, in which case the value
3318 -- of the attribute is determined using the J.4 rules. This choice
3319 -- seems the most useful, and is compatible with existing tests.
3321 elsif In_Instance
then
3324 -- Also allow an object of a generic type if extensions allowed
3325 -- and allow this for any type at all. (this may be obsolete ???)
3327 elsif (Is_Generic_Type
(P_Type
)
3328 or else Is_Generic_Actual_Type
(P_Type
))
3329 and then Extensions_Allowed
3335 -- Fall through if bad prefix
3338 ("prefix of % attribute must be object of discriminated type");
3344 when Attribute_Copy_Sign
=>
3345 Check_Floating_Point_Type_2
;
3346 Set_Etype
(N
, P_Base_Type
);
3347 Resolve
(E1
, P_Base_Type
);
3348 Resolve
(E2
, P_Base_Type
);
3354 when Attribute_Count
=> Count
:
3363 if Nkind_In
(P
, N_Identifier
, N_Expanded_Name
) then
3366 if Ekind
(Ent
) /= E_Entry
then
3367 Error_Attr
("invalid entry name", N
);
3370 elsif Nkind
(P
) = N_Indexed_Component
then
3371 if not Is_Entity_Name
(Prefix
(P
))
3372 or else No
(Entity
(Prefix
(P
)))
3373 or else Ekind
(Entity
(Prefix
(P
))) /= E_Entry_Family
3375 if Nkind
(Prefix
(P
)) = N_Selected_Component
3376 and then Present
(Entity
(Selector_Name
(Prefix
(P
))))
3377 and then Ekind
(Entity
(Selector_Name
(Prefix
(P
)))) =
3381 ("attribute % must apply to entry of current task", P
);
3384 Error_Attr
("invalid entry family name", P
);
3389 Ent
:= Entity
(Prefix
(P
));
3392 elsif Nkind
(P
) = N_Selected_Component
3393 and then Present
(Entity
(Selector_Name
(P
)))
3394 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Entry
3397 ("attribute % must apply to entry of current task", P
);
3400 Error_Attr
("invalid entry name", N
);
3404 for J
in reverse 0 .. Scope_Stack
.Last
loop
3405 S
:= Scope_Stack
.Table
(J
).Entity
;
3407 if S
= Scope
(Ent
) then
3408 if Nkind
(P
) = N_Expanded_Name
then
3409 Tsk
:= Entity
(Prefix
(P
));
3411 -- The prefix denotes either the task type, or else a
3412 -- single task whose task type is being analyzed.
3414 if (Is_Type
(Tsk
) and then Tsk
= S
)
3415 or else (not Is_Type
(Tsk
)
3416 and then Etype
(Tsk
) = S
3417 and then not (Comes_From_Source
(S
)))
3422 ("Attribute % must apply to entry of current task", N
);
3428 elsif Ekind
(Scope
(Ent
)) in Task_Kind
3430 not Ekind_In
(S
, E_Loop
, E_Block
, E_Entry
, E_Entry_Family
)
3432 Error_Attr
("Attribute % cannot appear in inner unit", N
);
3434 elsif Ekind
(Scope
(Ent
)) = E_Protected_Type
3435 and then not Has_Completion
(Scope
(Ent
))
3437 Error_Attr
("attribute % can only be used inside body", N
);
3441 if Is_Overloaded
(P
) then
3443 Index
: Interp_Index
;
3447 Get_First_Interp
(P
, Index
, It
);
3448 while Present
(It
.Nam
) loop
3449 if It
.Nam
= Ent
then
3452 -- Ada 2005 (AI-345): Do not consider primitive entry
3453 -- wrappers generated for task or protected types.
3455 elsif Ada_Version
>= Ada_2005
3456 and then not Comes_From_Source
(It
.Nam
)
3461 Error_Attr
("ambiguous entry name", N
);
3464 Get_Next_Interp
(Index
, It
);
3469 Set_Etype
(N
, Universal_Integer
);
3472 -----------------------
3473 -- Default_Bit_Order --
3474 -----------------------
3476 when Attribute_Default_Bit_Order
=> Default_Bit_Order
: declare
3477 Target_Default_Bit_Order
: System
.Bit_Order
;
3480 Check_Standard_Prefix
;
3482 if Bytes_Big_Endian
then
3483 Target_Default_Bit_Order
:= System
.High_Order_First
;
3485 Target_Default_Bit_Order
:= System
.Low_Order_First
;
3489 Make_Integer_Literal
(Loc
,
3490 UI_From_Int
(System
.Bit_Order
'Pos (Target_Default_Bit_Order
))));
3492 Set_Etype
(N
, Universal_Integer
);
3493 Set_Is_Static_Expression
(N
);
3494 end Default_Bit_Order
;
3496 ----------------------------------
3497 -- Default_Scalar_Storage_Order --
3498 ----------------------------------
3500 when Attribute_Default_Scalar_Storage_Order
=> Default_SSO
: declare
3501 RE_Default_SSO
: RE_Id
;
3504 Check_Standard_Prefix
;
3506 case Opt
.Default_SSO
is
3508 if Bytes_Big_Endian
then
3509 RE_Default_SSO
:= RE_High_Order_First
;
3511 RE_Default_SSO
:= RE_Low_Order_First
;
3515 RE_Default_SSO
:= RE_High_Order_First
;
3518 RE_Default_SSO
:= RE_Low_Order_First
;
3521 raise Program_Error
;
3524 Rewrite
(N
, New_Occurrence_Of
(RTE
(RE_Default_SSO
), Loc
));
3531 when Attribute_Definite
=>
3532 Legal_Formal_Attribute
;
3538 when Attribute_Delta
=>
3539 Check_Fixed_Point_Type_0
;
3540 Set_Etype
(N
, Universal_Real
);
3546 when Attribute_Denorm
=>
3547 Check_Floating_Point_Type_0
;
3548 Set_Etype
(N
, Standard_Boolean
);
3554 when Attribute_Deref
=>
3557 Resolve
(E1
, RTE
(RE_Address
));
3558 Set_Etype
(N
, P_Type
);
3560 ---------------------
3561 -- Descriptor_Size --
3562 ---------------------
3564 when Attribute_Descriptor_Size
=>
3567 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
3568 Error_Attr_P
("prefix of attribute % must denote a type");
3571 Set_Etype
(N
, Universal_Integer
);
3577 when Attribute_Digits
=>
3581 if not Is_Floating_Point_Type
(P_Type
)
3582 and then not Is_Decimal_Fixed_Point_Type
(P_Type
)
3585 ("prefix of % attribute must be float or decimal type");
3588 Set_Etype
(N
, Universal_Integer
);
3594 -- Also handles processing for Elab_Spec and Elab_Subp_Body
3596 when Attribute_Elab_Body |
3597 Attribute_Elab_Spec |
3598 Attribute_Elab_Subp_Body
=>
3601 Check_Unit_Name
(P
);
3602 Set_Etype
(N
, Standard_Void_Type
);
3604 -- We have to manually call the expander in this case to get
3605 -- the necessary expansion (normally attributes that return
3606 -- entities are not expanded).
3614 -- Shares processing with Elab_Body
3620 when Attribute_Elaborated
=>
3622 Check_Unit_Name
(P
);
3623 Set_Etype
(N
, Standard_Boolean
);
3629 when Attribute_Emax
=>
3630 Check_Floating_Point_Type_0
;
3631 Set_Etype
(N
, Universal_Integer
);
3637 when Attribute_Enabled
=>
3638 Check_Either_E0_Or_E1
;
3640 if Present
(E1
) then
3641 if not Is_Entity_Name
(E1
) or else No
(Entity
(E1
)) then
3642 Error_Msg_N
("entity name expected for Enabled attribute", E1
);
3647 if Nkind
(P
) /= N_Identifier
then
3648 Error_Msg_N
("identifier expected (check name)", P
);
3649 elsif Get_Check_Id
(Chars
(P
)) = No_Check_Id
then
3650 Error_Msg_N
("& is not a recognized check name", P
);
3653 Set_Etype
(N
, Standard_Boolean
);
3659 when Attribute_Enum_Rep
=> Enum_Rep
: declare
3661 if Present
(E1
) then
3663 Check_Discrete_Type
;
3664 Resolve
(E1
, P_Base_Type
);
3667 if not Is_Entity_Name
(P
)
3668 or else (not Is_Object
(Entity
(P
))
3669 and then Ekind
(Entity
(P
)) /= E_Enumeration_Literal
)
3672 ("prefix of % attribute must be " &
3673 "discrete type/object or enum literal");
3677 Set_Etype
(N
, Universal_Integer
);
3684 when Attribute_Enum_Val
=> Enum_Val
: begin
3688 if not Is_Enumeration_Type
(P_Type
) then
3689 Error_Attr_P
("prefix of % attribute must be enumeration type");
3692 -- If the enumeration type has a standard representation, the effect
3693 -- is the same as 'Val, so rewrite the attribute as a 'Val.
3695 if not Has_Non_Standard_Rep
(P_Base_Type
) then
3697 Make_Attribute_Reference
(Loc
,
3698 Prefix
=> Relocate_Node
(Prefix
(N
)),
3699 Attribute_Name
=> Name_Val
,
3700 Expressions
=> New_List
(Relocate_Node
(E1
))));
3701 Analyze_And_Resolve
(N
, P_Base_Type
);
3703 -- Non-standard representation case (enumeration with holes)
3707 Resolve
(E1
, Any_Integer
);
3708 Set_Etype
(N
, P_Base_Type
);
3716 when Attribute_Epsilon
=>
3717 Check_Floating_Point_Type_0
;
3718 Set_Etype
(N
, Universal_Real
);
3724 when Attribute_Exponent
=>
3725 Check_Floating_Point_Type_1
;
3726 Set_Etype
(N
, Universal_Integer
);
3727 Resolve
(E1
, P_Base_Type
);
3733 when Attribute_External_Tag
=>
3737 Set_Etype
(N
, Standard_String
);
3739 if not Is_Tagged_Type
(P_Type
) then
3740 Error_Attr_P
("prefix of % attribute must be tagged");
3747 when Attribute_Fast_Math
=>
3748 Check_Standard_Prefix
;
3749 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(Fast_Math
), Loc
));
3755 when Attribute_First
=>
3756 Check_Array_Or_Scalar_Type
;
3757 Bad_Attribute_For_Predicate
;
3763 when Attribute_First_Bit
=>
3765 Set_Etype
(N
, Universal_Integer
);
3771 when Attribute_First_Valid
=>
3772 Check_First_Last_Valid
;
3773 Set_Etype
(N
, P_Type
);
3779 when Attribute_Fixed_Value
=>
3781 Check_Fixed_Point_Type
;
3782 Resolve
(E1
, Any_Integer
);
3783 Set_Etype
(N
, P_Base_Type
);
3789 when Attribute_Floor
=>
3790 Check_Floating_Point_Type_1
;
3791 Set_Etype
(N
, P_Base_Type
);
3792 Resolve
(E1
, P_Base_Type
);
3798 when Attribute_Fore
=>
3799 Check_Fixed_Point_Type_0
;
3800 Set_Etype
(N
, Universal_Integer
);
3806 when Attribute_Fraction
=>
3807 Check_Floating_Point_Type_1
;
3808 Set_Etype
(N
, P_Base_Type
);
3809 Resolve
(E1
, P_Base_Type
);
3815 when Attribute_From_Any
=>
3817 Check_PolyORB_Attribute
;
3818 Set_Etype
(N
, P_Base_Type
);
3820 -----------------------
3821 -- Has_Access_Values --
3822 -----------------------
3824 when Attribute_Has_Access_Values
=>
3827 Set_Etype
(N
, Standard_Boolean
);
3829 ----------------------
3830 -- Has_Same_Storage --
3831 ----------------------
3833 when Attribute_Has_Same_Storage
=>
3836 -- The arguments must be objects of any type
3838 Analyze_And_Resolve
(P
);
3839 Analyze_And_Resolve
(E1
);
3840 Check_Object_Reference
(P
);
3841 Check_Object_Reference
(E1
);
3842 Set_Etype
(N
, Standard_Boolean
);
3844 -----------------------
3845 -- Has_Tagged_Values --
3846 -----------------------
3848 when Attribute_Has_Tagged_Values
=>
3851 Set_Etype
(N
, Standard_Boolean
);
3853 -----------------------
3854 -- Has_Discriminants --
3855 -----------------------
3857 when Attribute_Has_Discriminants
=>
3858 Legal_Formal_Attribute
;
3864 when Attribute_Identity
=>
3868 if Etype
(P
) = Standard_Exception_Type
then
3869 Set_Etype
(N
, RTE
(RE_Exception_Id
));
3871 -- Ada 2005 (AI-345): Attribute 'Identity may be applied to task
3872 -- interface class-wide types.
3874 elsif Is_Task_Type
(Etype
(P
))
3875 or else (Is_Access_Type
(Etype
(P
))
3876 and then Is_Task_Type
(Designated_Type
(Etype
(P
))))
3877 or else (Ada_Version
>= Ada_2005
3878 and then Ekind
(Etype
(P
)) = E_Class_Wide_Type
3879 and then Is_Interface
(Etype
(P
))
3880 and then Is_Task_Interface
(Etype
(P
)))
3883 Set_Etype
(N
, RTE
(RO_AT_Task_Id
));
3886 if Ada_Version
>= Ada_2005
then
3888 ("prefix of % attribute must be an exception, a " &
3889 "task or a task interface class-wide object");
3892 ("prefix of % attribute must be a task or an exception");
3900 when Attribute_Image
=> Image
:
3902 Check_SPARK_05_Restriction_On_Attribute
;
3904 Set_Etype
(N
, Standard_String
);
3906 if Is_Real_Type
(P_Type
) then
3907 if Ada_Version
= Ada_83
and then Comes_From_Source
(N
) then
3908 Error_Msg_Name_1
:= Aname
;
3910 ("(Ada 83) % attribute not allowed for real types", N
);
3914 if Is_Enumeration_Type
(P_Type
) then
3915 Check_Restriction
(No_Enumeration_Maps
, N
);
3919 Resolve
(E1
, P_Base_Type
);
3921 Validate_Non_Static_Attribute_Function_Call
;
3923 -- Check restriction No_Fixed_IO. Note the check of Comes_From_Source
3924 -- to avoid giving a duplicate message for Img expanded into Image.
3926 if Restriction_Check_Required
(No_Fixed_IO
)
3927 and then Comes_From_Source
(N
)
3928 and then Is_Fixed_Point_Type
(P_Type
)
3930 Check_Restriction
(No_Fixed_IO
, P
);
3938 when Attribute_Img
=> Img
:
3941 Set_Etype
(N
, Standard_String
);
3943 if not Is_Scalar_Type
(P_Type
)
3944 or else (Is_Entity_Name
(P
) and then Is_Type
(Entity
(P
)))
3947 ("prefix of % attribute must be scalar object name");
3952 -- Check restriction No_Fixed_IO
3954 if Restriction_Check_Required
(No_Fixed_IO
)
3955 and then Is_Fixed_Point_Type
(P_Type
)
3957 Check_Restriction
(No_Fixed_IO
, P
);
3965 when Attribute_Input
=>
3967 Check_Stream_Attribute
(TSS_Stream_Input
);
3968 Set_Etype
(N
, P_Base_Type
);
3974 when Attribute_Integer_Value
=>
3977 Resolve
(E1
, Any_Fixed
);
3979 -- Signal an error if argument type is not a specific fixed-point
3980 -- subtype. An error has been signalled already if the argument
3981 -- was not of a fixed-point type.
3983 if Etype
(E1
) = Any_Fixed
and then not Error_Posted
(E1
) then
3984 Error_Attr
("argument of % must be of a fixed-point type", E1
);
3987 Set_Etype
(N
, P_Base_Type
);
3993 when Attribute_Invalid_Value
=>
3996 Set_Etype
(N
, P_Base_Type
);
3997 Invalid_Value_Used
:= True;
4003 when Attribute_Large
=>
4006 Set_Etype
(N
, Universal_Real
);
4012 when Attribute_Last
=>
4013 Check_Array_Or_Scalar_Type
;
4014 Bad_Attribute_For_Predicate
;
4020 when Attribute_Last_Bit
=>
4022 Set_Etype
(N
, Universal_Integer
);
4028 when Attribute_Last_Valid
=>
4029 Check_First_Last_Valid
;
4030 Set_Etype
(N
, P_Type
);
4036 when Attribute_Leading_Part
=>
4037 Check_Floating_Point_Type_2
;
4038 Set_Etype
(N
, P_Base_Type
);
4039 Resolve
(E1
, P_Base_Type
);
4040 Resolve
(E2
, Any_Integer
);
4046 when Attribute_Length
=>
4048 Set_Etype
(N
, Universal_Integer
);
4054 when Attribute_Library_Level
=>
4057 if not Is_Entity_Name
(P
) then
4058 Error_Attr_P
("prefix of % attribute must be an entity name");
4061 if not Inside_A_Generic
then
4062 Set_Boolean_Result
(N
,
4063 Is_Library_Level_Entity
(Entity
(P
)));
4066 Set_Etype
(N
, Standard_Boolean
);
4072 when Attribute_Lock_Free
=>
4074 Set_Etype
(N
, Standard_Boolean
);
4076 if not Is_Protected_Type
(P_Type
) then
4078 ("prefix of % attribute must be a protected object");
4085 when Attribute_Loop_Entry
=> Loop_Entry
: declare
4086 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
);
4087 -- Inspect the prefix for any uses of entities declared within the
4088 -- related loop. Loop_Id denotes the loop identifier.
4090 --------------------------------
4091 -- Check_References_In_Prefix --
4092 --------------------------------
4094 procedure Check_References_In_Prefix
(Loop_Id
: Entity_Id
) is
4095 Loop_Decl
: constant Node_Id
:= Label_Construct
(Parent
(Loop_Id
));
4097 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4098 -- Determine whether a reference mentions an entity declared
4099 -- within the related loop.
4101 function Declared_Within
(Nod
: Node_Id
) return Boolean;
4102 -- Determine whether Nod appears in the subtree of Loop_Decl
4104 ---------------------
4105 -- Check_Reference --
4106 ---------------------
4108 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4110 if Nkind
(Nod
) = N_Identifier
4111 and then Present
(Entity
(Nod
))
4112 and then Declared_Within
(Declaration_Node
(Entity
(Nod
)))
4115 ("prefix of attribute % cannot reference local entities",
4121 end Check_Reference
;
4123 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4125 ---------------------
4126 -- Declared_Within --
4127 ---------------------
4129 function Declared_Within
(Nod
: Node_Id
) return Boolean is
4134 while Present
(Stmt
) loop
4135 if Stmt
= Loop_Decl
then
4138 -- Prevent the search from going too far
4140 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4144 Stmt
:= Parent
(Stmt
);
4148 end Declared_Within
;
4150 -- Start of processing for Check_Prefix_For_Local_References
4153 Check_References
(P
);
4154 end Check_References_In_Prefix
;
4158 Context
: constant Node_Id
:= Parent
(N
);
4160 Enclosing_Loop
: Node_Id
;
4161 Loop_Id
: Entity_Id
:= Empty
;
4164 Enclosing_Pragma
: Node_Id
:= Empty
;
4166 -- Start of processing for Loop_Entry
4171 -- Set the type of the attribute now to ensure the successfull
4172 -- continuation of analysis even if the attribute is misplaced.
4174 Set_Etype
(Attr
, P_Type
);
4176 -- Attribute 'Loop_Entry may appear in several flavors:
4178 -- * Prefix'Loop_Entry - in this form, the attribute applies to the
4179 -- nearest enclosing loop.
4181 -- * Prefix'Loop_Entry (Expr) - depending on what Expr denotes, the
4182 -- attribute may be related to a loop denoted by label Expr or
4183 -- the prefix may denote an array object and Expr may act as an
4184 -- indexed component.
4186 -- * Prefix'Loop_Entry (Expr1, ..., ExprN) - the attribute applies
4187 -- to the nearest enclosing loop, all expressions are part of
4188 -- an indexed component.
4190 -- * Prefix'Loop_Entry (Expr) (...) (...) - depending on what Expr
4191 -- denotes, the attribute may be related to a loop denoted by
4192 -- label Expr or the prefix may denote a multidimensional array
4193 -- array object and Expr along with the rest of the expressions
4194 -- may act as indexed components.
4196 -- Regardless of variations, the attribute reference does not have an
4197 -- expression list. Instead, all available expressions are stored as
4198 -- indexed components.
4200 -- When the attribute is part of an indexed component, find the first
4201 -- expression as it will determine the semantics of 'Loop_Entry.
4203 if Nkind
(Context
) = N_Indexed_Component
then
4204 E1
:= First
(Expressions
(Context
));
4207 -- The attribute reference appears in the following form:
4209 -- Prefix'Loop_Entry (Exp1, Expr2, ..., ExprN) [(...)]
4211 -- In this case, the loop name is omitted and no rewriting is
4214 if Present
(E2
) then
4217 -- The form of the attribute is:
4219 -- Prefix'Loop_Entry (Expr) [(...)]
4221 -- If Expr denotes a loop entry, the whole attribute and indexed
4222 -- component will have to be rewritten to reflect this relation.
4225 pragma Assert
(Present
(E1
));
4227 -- Do not expand the expression as it may have side effects.
4228 -- Simply preanalyze to determine whether it is a loop name or
4231 Preanalyze_And_Resolve
(E1
);
4233 if Is_Entity_Name
(E1
)
4234 and then Present
(Entity
(E1
))
4235 and then Ekind
(Entity
(E1
)) = E_Loop
4237 Loop_Id
:= Entity
(E1
);
4239 -- Transform the attribute and enclosing indexed component
4241 Set_Expressions
(N
, Expressions
(Context
));
4242 Rewrite
(Context
, N
);
4243 Set_Etype
(Context
, P_Type
);
4250 -- The prefix must denote an object
4252 if not Is_Object_Reference
(P
) then
4253 Error_Attr_P
("prefix of attribute % must denote an object");
4256 -- The prefix cannot be of a limited type because the expansion of
4257 -- Loop_Entry must create a constant initialized by the evaluated
4260 if Is_Limited_View
(Etype
(P
)) then
4261 Error_Attr_P
("prefix of attribute % cannot be limited");
4264 -- Climb the parent chain to verify the location of the attribute and
4265 -- find the enclosing loop.
4268 while Present
(Stmt
) loop
4270 -- Locate the corresponding enclosing pragma. Note that in the
4271 -- case of Assert[And_Cut] and Assume, we have already checked
4272 -- that the pragma appears in an appropriate loop location.
4274 if Nkind
(Original_Node
(Stmt
)) = N_Pragma
4275 and then Nam_In
(Pragma_Name
(Original_Node
(Stmt
)),
4276 Name_Loop_Invariant
,
4279 Name_Assert_And_Cut
,
4282 Enclosing_Pragma
:= Original_Node
(Stmt
);
4284 -- Locate the enclosing loop (if any). Note that Ada 2012 array
4285 -- iteration may be expanded into several nested loops, we are
4286 -- interested in the outermost one which has the loop identifier,
4287 -- and comes from source.
4289 elsif Nkind
(Stmt
) = N_Loop_Statement
4290 and then Present
(Identifier
(Stmt
))
4291 and then Comes_From_Source
(Original_Node
(Stmt
))
4292 and then Nkind
(Original_Node
(Stmt
)) = N_Loop_Statement
4294 Enclosing_Loop
:= Stmt
;
4296 -- The original attribute reference may lack a loop name. Use
4297 -- the name of the enclosing loop because it is the related
4300 if No
(Loop_Id
) then
4301 Loop_Id
:= Entity
(Identifier
(Enclosing_Loop
));
4306 -- Prevent the search from going too far
4308 elsif Is_Body_Or_Package_Declaration
(Stmt
) then
4312 Stmt
:= Parent
(Stmt
);
4315 -- Loop_Entry must appear within a Loop_Assertion pragma (Assert,
4316 -- Assert_And_Cut, Assume count as loop assertion pragmas for this
4317 -- purpose if they appear in an appropriate location in a loop,
4318 -- which was already checked by the top level pragma circuit).
4320 if No
(Enclosing_Pragma
) then
4321 Error_Attr
("attribute% must appear within appropriate pragma", N
);
4324 -- A Loop_Entry that applies to a given loop statement must not
4325 -- appear within a body of accept statement, if this construct is
4326 -- itself enclosed by the given loop statement.
4328 for Index
in reverse 0 .. Scope_Stack
.Last
loop
4329 Scop
:= Scope_Stack
.Table
(Index
).Entity
;
4331 if Ekind
(Scop
) = E_Loop
and then Scop
= Loop_Id
then
4333 elsif Ekind_In
(Scop
, E_Block
, E_Loop
, E_Return_Statement
) then
4337 ("attribute % cannot appear in body or accept statement", N
);
4342 -- The prefix cannot mention entities declared within the related
4343 -- loop because they will not be visible once the prefix is moved
4344 -- outside the loop.
4346 Check_References_In_Prefix
(Loop_Id
);
4348 -- The prefix must denote a static entity if the pragma does not
4349 -- apply to the innermost enclosing loop statement, or if it appears
4350 -- within a potentially unevaluated epxression.
4352 if Is_Entity_Name
(P
)
4353 or else Nkind
(Parent
(P
)) = N_Object_Renaming_Declaration
4357 elsif Present
(Enclosing_Loop
)
4358 and then Entity
(Identifier
(Enclosing_Loop
)) /= Loop_Id
4361 ("prefix of attribute % that applies to outer loop must denote "
4364 elsif Is_Potentially_Unevaluated
(P
) then
4368 -- Replace the Loop_Entry attribute reference by its prefix if the
4369 -- related pragma is ignored. This transformation is OK with respect
4370 -- to typing because Loop_Entry's type is that of its prefix. This
4371 -- early transformation also avoids the generation of a useless loop
4374 if Is_Ignored
(Enclosing_Pragma
) then
4375 Rewrite
(N
, Relocate_Node
(P
));
4378 Preanalyze_And_Resolve
(P
);
4385 when Attribute_Machine
=>
4386 Check_Floating_Point_Type_1
;
4387 Set_Etype
(N
, P_Base_Type
);
4388 Resolve
(E1
, P_Base_Type
);
4394 when Attribute_Machine_Emax
=>
4395 Check_Floating_Point_Type_0
;
4396 Set_Etype
(N
, Universal_Integer
);
4402 when Attribute_Machine_Emin
=>
4403 Check_Floating_Point_Type_0
;
4404 Set_Etype
(N
, Universal_Integer
);
4406 ----------------------
4407 -- Machine_Mantissa --
4408 ----------------------
4410 when Attribute_Machine_Mantissa
=>
4411 Check_Floating_Point_Type_0
;
4412 Set_Etype
(N
, Universal_Integer
);
4414 -----------------------
4415 -- Machine_Overflows --
4416 -----------------------
4418 when Attribute_Machine_Overflows
=>
4421 Set_Etype
(N
, Standard_Boolean
);
4427 when Attribute_Machine_Radix
=>
4430 Set_Etype
(N
, Universal_Integer
);
4432 ----------------------
4433 -- Machine_Rounding --
4434 ----------------------
4436 when Attribute_Machine_Rounding
=>
4437 Check_Floating_Point_Type_1
;
4438 Set_Etype
(N
, P_Base_Type
);
4439 Resolve
(E1
, P_Base_Type
);
4441 --------------------
4442 -- Machine_Rounds --
4443 --------------------
4445 when Attribute_Machine_Rounds
=>
4448 Set_Etype
(N
, Standard_Boolean
);
4454 when Attribute_Machine_Size
=>
4457 Check_Not_Incomplete_Type
;
4458 Set_Etype
(N
, Universal_Integer
);
4464 when Attribute_Mantissa
=>
4467 Set_Etype
(N
, Universal_Integer
);
4473 when Attribute_Max
=>
4476 ----------------------------------
4477 -- Max_Alignment_For_Allocation --
4478 ----------------------------------
4480 when Attribute_Max_Size_In_Storage_Elements
=>
4481 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4483 ----------------------------------
4484 -- Max_Size_In_Storage_Elements --
4485 ----------------------------------
4487 when Attribute_Max_Alignment_For_Allocation
=>
4488 Max_Alignment_For_Allocation_Max_Size_In_Storage_Elements
;
4490 -----------------------
4491 -- Maximum_Alignment --
4492 -----------------------
4494 when Attribute_Maximum_Alignment
=>
4495 Standard_Attribute
(Ttypes
.Maximum_Alignment
);
4497 --------------------
4498 -- Mechanism_Code --
4499 --------------------
4501 when Attribute_Mechanism_Code
=>
4502 if not Is_Entity_Name
(P
)
4503 or else not Is_Subprogram
(Entity
(P
))
4505 Error_Attr_P
("prefix of % attribute must be subprogram");
4508 Check_Either_E0_Or_E1
;
4510 if Present
(E1
) then
4511 Resolve
(E1
, Any_Integer
);
4512 Set_Etype
(E1
, Standard_Integer
);
4514 if not Is_OK_Static_Expression
(E1
) then
4515 Flag_Non_Static_Expr
4516 ("expression for parameter number must be static!", E1
);
4519 elsif UI_To_Int
(Intval
(E1
)) > Number_Formals
(Entity
(P
))
4520 or else UI_To_Int
(Intval
(E1
)) < 0
4522 Error_Attr
("invalid parameter number for % attribute", E1
);
4526 Set_Etype
(N
, Universal_Integer
);
4532 when Attribute_Min
=>
4539 when Attribute_Mod
=>
4541 -- Note: this attribute is only allowed in Ada 2005 mode, but
4542 -- we do not need to test that here, since Mod is only recognized
4543 -- as an attribute name in Ada 2005 mode during the parse.
4546 Check_Modular_Integer_Type
;
4547 Resolve
(E1
, Any_Integer
);
4548 Set_Etype
(N
, P_Base_Type
);
4554 when Attribute_Model
=>
4555 Check_Floating_Point_Type_1
;
4556 Set_Etype
(N
, P_Base_Type
);
4557 Resolve
(E1
, P_Base_Type
);
4563 when Attribute_Model_Emin
=>
4564 Check_Floating_Point_Type_0
;
4565 Set_Etype
(N
, Universal_Integer
);
4571 when Attribute_Model_Epsilon
=>
4572 Check_Floating_Point_Type_0
;
4573 Set_Etype
(N
, Universal_Real
);
4575 --------------------
4576 -- Model_Mantissa --
4577 --------------------
4579 when Attribute_Model_Mantissa
=>
4580 Check_Floating_Point_Type_0
;
4581 Set_Etype
(N
, Universal_Integer
);
4587 when Attribute_Model_Small
=>
4588 Check_Floating_Point_Type_0
;
4589 Set_Etype
(N
, Universal_Real
);
4595 when Attribute_Modulus
=>
4597 Check_Modular_Integer_Type
;
4598 Set_Etype
(N
, Universal_Integer
);
4600 --------------------
4601 -- Null_Parameter --
4602 --------------------
4604 when Attribute_Null_Parameter
=> Null_Parameter
: declare
4605 Parnt
: constant Node_Id
:= Parent
(N
);
4606 GParnt
: constant Node_Id
:= Parent
(Parnt
);
4608 procedure Bad_Null_Parameter
(Msg
: String);
4609 -- Used if bad Null parameter attribute node is found. Issues
4610 -- given error message, and also sets the type to Any_Type to
4611 -- avoid blowups later on from dealing with a junk node.
4613 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
);
4614 -- Called to check that Proc_Ent is imported subprogram
4616 ------------------------
4617 -- Bad_Null_Parameter --
4618 ------------------------
4620 procedure Bad_Null_Parameter
(Msg
: String) is
4622 Error_Msg_N
(Msg
, N
);
4623 Set_Etype
(N
, Any_Type
);
4624 end Bad_Null_Parameter
;
4626 ----------------------
4627 -- Must_Be_Imported --
4628 ----------------------
4630 procedure Must_Be_Imported
(Proc_Ent
: Entity_Id
) is
4631 Pent
: constant Entity_Id
:= Ultimate_Alias
(Proc_Ent
);
4634 -- Ignore check if procedure not frozen yet (we will get
4635 -- another chance when the default parameter is reanalyzed)
4637 if not Is_Frozen
(Pent
) then
4640 elsif not Is_Imported
(Pent
) then
4642 ("Null_Parameter can only be used with imported subprogram");
4647 end Must_Be_Imported
;
4649 -- Start of processing for Null_Parameter
4654 Set_Etype
(N
, P_Type
);
4656 -- Case of attribute used as default expression
4658 if Nkind
(Parnt
) = N_Parameter_Specification
then
4659 Must_Be_Imported
(Defining_Entity
(GParnt
));
4661 -- Case of attribute used as actual for subprogram (positional)
4663 elsif Nkind
(Parnt
) in N_Subprogram_Call
4664 and then Is_Entity_Name
(Name
(Parnt
))
4666 Must_Be_Imported
(Entity
(Name
(Parnt
)));
4668 -- Case of attribute used as actual for subprogram (named)
4670 elsif Nkind
(Parnt
) = N_Parameter_Association
4671 and then Nkind
(GParnt
) in N_Subprogram_Call
4672 and then Is_Entity_Name
(Name
(GParnt
))
4674 Must_Be_Imported
(Entity
(Name
(GParnt
)));
4676 -- Not an allowed case
4680 ("Null_Parameter must be actual or default parameter");
4688 when Attribute_Object_Size
=>
4691 Check_Not_Incomplete_Type
;
4692 Set_Etype
(N
, Universal_Integer
);
4698 when Attribute_Old
=> Old
: declare
4699 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
);
4700 -- Inspect the contents of the prefix and detect illegal uses of a
4701 -- nested 'Old, attribute 'Result or a use of an entity declared in
4702 -- the related postcondition expression. Subp_Id is the subprogram to
4703 -- which the related postcondition applies.
4705 --------------------------------
4706 -- Check_References_In_Prefix --
4707 --------------------------------
4709 procedure Check_References_In_Prefix
(Subp_Id
: Entity_Id
) is
4710 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
;
4711 -- Detect attribute 'Old, attribute 'Result of a use of an entity
4712 -- and perform the appropriate semantic check.
4714 ---------------------
4715 -- Check_Reference --
4716 ---------------------
4718 function Check_Reference
(Nod
: Node_Id
) return Traverse_Result
is
4720 -- Attributes 'Old and 'Result cannot appear in the prefix of
4721 -- another attribute 'Old.
4723 if Nkind
(Nod
) = N_Attribute_Reference
4724 and then Nam_In
(Attribute_Name
(Nod
), Name_Old
,
4727 Error_Msg_Name_1
:= Attribute_Name
(Nod
);
4728 Error_Msg_Name_2
:= Name_Old
;
4730 ("attribute % cannot appear in the prefix of attribute %",
4734 -- Entities mentioned within the prefix of attribute 'Old must
4735 -- be global to the related postcondition. If this is not the
4736 -- case, then the scope of the local entity is nested within
4737 -- that of the subprogram.
4739 elsif Is_Entity_Name
(Nod
)
4740 and then Present
(Entity
(Nod
))
4741 and then Scope_Within
(Scope
(Entity
(Nod
)), Subp_Id
)
4744 ("prefix of attribute % cannot reference local entities",
4748 -- Otherwise keep inspecting the prefix
4753 end Check_Reference
;
4755 procedure Check_References
is new Traverse_Proc
(Check_Reference
);
4757 -- Start of processing for Check_References_In_Prefix
4760 Check_References
(P
);
4761 end Check_References_In_Prefix
;
4766 Pref_Id
: Entity_Id
;
4767 Pref_Typ
: Entity_Id
;
4768 Spec_Id
: Entity_Id
;
4770 -- Start of processing for Old
4773 -- The attribute reference is a primary. If any expressions follow,
4774 -- then the attribute reference is an indexable object. Transform the
4775 -- attribute into an indexed component and analyze it.
4777 if Present
(E1
) then
4779 Make_Indexed_Component
(Loc
,
4781 Make_Attribute_Reference
(Loc
,
4782 Prefix
=> Relocate_Node
(P
),
4783 Attribute_Name
=> Name_Old
),
4784 Expressions
=> Expressions
(N
)));
4789 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
4791 -- The aspect or pragma where attribute 'Old resides should be
4792 -- associated with a subprogram declaration or a body. If this is not
4793 -- the case, then the aspect or pragma is illegal. Return as analysis
4794 -- cannot be carried out.
4800 -- The prefix must be preanalyzed as the full analysis will take
4801 -- place during expansion.
4803 Preanalyze_And_Resolve
(P
);
4805 -- Ensure that the prefix does not contain attributes 'Old or 'Result
4807 Check_References_In_Prefix
(Spec_Id
);
4809 -- Set the type of the attribute now to prevent cascaded errors
4811 Pref_Typ
:= Etype
(P
);
4812 Set_Etype
(N
, Pref_Typ
);
4816 if Is_Limited_Type
(Pref_Typ
) then
4817 Error_Attr
("attribute % cannot apply to limited objects", P
);
4820 -- The prefix is a simple name
4822 if Is_Entity_Name
(P
) and then Present
(Entity
(P
)) then
4823 Pref_Id
:= Entity
(P
);
4825 -- Emit a warning when the prefix is a constant. Note that the use
4826 -- of Error_Attr would reset the type of N to Any_Type even though
4827 -- this is a warning. Use Error_Msg_XXX instead.
4829 if Is_Constant_Object
(Pref_Id
) then
4830 Error_Msg_Name_1
:= Name_Old
;
4832 ("??attribute % applied to constant has no effect", P
);
4835 -- Otherwise the prefix is not a simple name
4838 -- Ensure that the prefix of attribute 'Old is an entity when it
4839 -- is potentially unevaluated (6.1.1 (27/3)).
4841 if Is_Potentially_Unevaluated
(N
) then
4844 -- Detect a possible infinite recursion when the prefix denotes
4845 -- the related function.
4847 -- function Func (...) return ...
4848 -- with Post => Func'Old ...;
4850 elsif Nkind
(P
) = N_Function_Call
then
4851 Pref_Id
:= Entity
(Name
(P
));
4853 if Ekind_In
(Spec_Id
, E_Function
, E_Generic_Function
)
4854 and then Pref_Id
= Spec_Id
4856 Error_Msg_Warn
:= SPARK_Mode
/= On
;
4857 Error_Msg_N
("!possible infinite recursion<<", P
);
4858 Error_Msg_N
("\!??Storage_Error ]<<", P
);
4862 -- The prefix of attribute 'Old may refer to a component of a
4863 -- formal parameter. In this case its expansion may generate
4864 -- actual subtypes that are referenced in an inner context and
4865 -- that must be elaborated within the subprogram itself. If the
4866 -- prefix includes a function call, it may involve finalization
4867 -- actions that should be inserted when the attribute has been
4868 -- rewritten as a declaration. Create a declaration for the prefix
4869 -- and insert it at the start of the enclosing subprogram. This is
4870 -- an expansion activity that has to be performed now to prevent
4871 -- out-of-order issues.
4873 -- This expansion is both harmful and not needed in SPARK mode,
4874 -- since the formal verification backend relies on the types of
4875 -- nodes (hence is not robust w.r.t. a change to base type here),
4876 -- and does not suffer from the out-of-order issue described
4877 -- above. Thus, this expansion is skipped in SPARK mode.
4879 if not GNATprove_Mode
then
4880 Pref_Typ
:= Base_Type
(Pref_Typ
);
4881 Set_Etype
(N
, Pref_Typ
);
4882 Set_Etype
(P
, Pref_Typ
);
4884 Analyze_Dimension
(N
);
4890 ----------------------
4891 -- Overlaps_Storage --
4892 ----------------------
4894 when Attribute_Overlaps_Storage
=>
4897 -- Both arguments must be objects of any type
4899 Analyze_And_Resolve
(P
);
4900 Analyze_And_Resolve
(E1
);
4901 Check_Object_Reference
(P
);
4902 Check_Object_Reference
(E1
);
4903 Set_Etype
(N
, Standard_Boolean
);
4909 when Attribute_Output
=>
4911 Check_Stream_Attribute
(TSS_Stream_Output
);
4912 Set_Etype
(N
, Standard_Void_Type
);
4913 Resolve
(N
, Standard_Void_Type
);
4919 when Attribute_Partition_ID
=> Partition_Id
:
4923 if P_Type
/= Any_Type
then
4924 if not Is_Library_Level_Entity
(Entity
(P
)) then
4926 ("prefix of % attribute must be library-level entity");
4928 -- The defining entity of prefix should not be declared inside a
4929 -- Pure unit. RM E.1(8). Is_Pure was set during declaration.
4931 elsif Is_Entity_Name
(P
)
4932 and then Is_Pure
(Entity
(P
))
4934 Error_Attr_P
("prefix of% attribute must not be declared pure");
4938 Set_Etype
(N
, Universal_Integer
);
4941 -------------------------
4942 -- Passed_By_Reference --
4943 -------------------------
4945 when Attribute_Passed_By_Reference
=>
4948 Set_Etype
(N
, Standard_Boolean
);
4954 when Attribute_Pool_Address
=>
4956 Set_Etype
(N
, RTE
(RE_Address
));
4962 when Attribute_Pos
=>
4963 Check_Discrete_Type
;
4966 if Is_Boolean_Type
(P_Type
) then
4967 Error_Msg_Name_1
:= Aname
;
4968 Error_Msg_Name_2
:= Chars
(P_Type
);
4969 Check_SPARK_05_Restriction
4970 ("attribute% is not allowed for type%", P
);
4973 Resolve
(E1
, P_Base_Type
);
4974 Set_Etype
(N
, Universal_Integer
);
4980 when Attribute_Position
=>
4982 Set_Etype
(N
, Universal_Integer
);
4988 when Attribute_Pred
=>
4992 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
4993 Error_Msg_Name_1
:= Aname
;
4994 Error_Msg_Name_2
:= Chars
(P_Type
);
4995 Check_SPARK_05_Restriction
4996 ("attribute% is not allowed for type%", P
);
4999 Resolve
(E1
, P_Base_Type
);
5000 Set_Etype
(N
, P_Base_Type
);
5002 -- Since Pred works on the base type, we normally do no check for the
5003 -- floating-point case, since the base type is unconstrained. But we
5004 -- make an exception in Check_Float_Overflow mode.
5006 if Is_Floating_Point_Type
(P_Type
) then
5007 if not Range_Checks_Suppressed
(P_Base_Type
) then
5008 Set_Do_Range_Check
(E1
);
5011 -- If not modular type, test for overflow check required
5014 if not Is_Modular_Integer_Type
(P_Type
)
5015 and then not Range_Checks_Suppressed
(P_Base_Type
)
5017 Enable_Range_Check
(E1
);
5025 -- Ada 2005 (AI-327): Dynamic ceiling priorities
5027 when Attribute_Priority
=>
5028 if Ada_Version
< Ada_2005
then
5029 Error_Attr
("% attribute is allowed only in Ada 2005 mode", P
);
5034 -- The prefix must be a protected object (AARM D.5.2 (2/2))
5038 if Is_Protected_Type
(Etype
(P
))
5039 or else (Is_Access_Type
(Etype
(P
))
5040 and then Is_Protected_Type
(Designated_Type
(Etype
(P
))))
5042 Resolve
(P
, Etype
(P
));
5044 Error_Attr_P
("prefix of % attribute must be a protected object");
5047 Set_Etype
(N
, Standard_Integer
);
5049 -- Must be called from within a protected procedure or entry of the
5050 -- protected object.
5057 while S
/= Etype
(P
)
5058 and then S
/= Standard_Standard
5063 if S
= Standard_Standard
then
5064 Error_Attr
("the attribute % is only allowed inside protected "
5069 Validate_Non_Static_Attribute_Function_Call
;
5075 when Attribute_Range
=>
5076 Check_Array_Or_Scalar_Type
;
5077 Bad_Attribute_For_Predicate
;
5079 if Ada_Version
= Ada_83
5080 and then Is_Scalar_Type
(P_Type
)
5081 and then Comes_From_Source
(N
)
5084 ("(Ada 83) % attribute not allowed for scalar type", P
);
5091 when Attribute_Result
=> Result
: declare
5092 function Denote_Same_Function
5093 (Pref_Id
: Entity_Id
;
5094 Spec_Id
: Entity_Id
) return Boolean;
5095 -- Determine whether the entity of the prefix Pref_Id denotes the
5096 -- same entity as that of the related subprogram Spec_Id.
5098 --------------------------
5099 -- Denote_Same_Function --
5100 --------------------------
5102 function Denote_Same_Function
5103 (Pref_Id
: Entity_Id
;
5104 Spec_Id
: Entity_Id
) return Boolean
5106 Subp_Spec
: constant Node_Id
:= Parent
(Spec_Id
);
5109 -- The prefix denotes the related subprogram
5111 if Pref_Id
= Spec_Id
then
5114 -- Account for a special case when attribute 'Result appears in
5115 -- the postcondition of a generic function.
5118 -- function Gen_Func return ...
5119 -- with Post => Gen_Func'Result ...;
5121 -- When the generic function is instantiated, the Chars field of
5122 -- the instantiated prefix still denotes the name of the generic
5123 -- function. Note that any preemptive transformation is impossible
5124 -- without a proper analysis. The structure of the wrapper package
5127 -- package Anon_Gen_Pack is
5128 -- <subtypes and renamings>
5129 -- function Subp_Decl return ...; -- (!)
5130 -- pragma Postcondition (Gen_Func'Result ...); -- (!)
5131 -- function Gen_Func ... renames Subp_Decl;
5132 -- end Anon_Gen_Pack;
5134 elsif Nkind
(Subp_Spec
) = N_Function_Specification
5135 and then Present
(Generic_Parent
(Subp_Spec
))
5136 and then Ekind_In
(Pref_Id
, E_Generic_Function
, E_Function
)
5138 if Generic_Parent
(Subp_Spec
) = Pref_Id
then
5141 elsif Present
(Alias
(Pref_Id
))
5142 and then Alias
(Pref_Id
) = Spec_Id
5148 -- Otherwise the prefix does not denote the related subprogram
5151 end Denote_Same_Function
;
5156 Pref_Id
: Entity_Id
;
5157 Spec_Id
: Entity_Id
;
5159 -- Start of processing for Result
5162 -- The attribute reference is a primary. If any expressions follow,
5163 -- then the attribute reference is an indexable object. Transform the
5164 -- attribute into an indexed component and analyze it.
5166 if Present
(E1
) then
5168 Make_Indexed_Component
(Loc
,
5170 Make_Attribute_Reference
(Loc
,
5171 Prefix
=> Relocate_Node
(P
),
5172 Attribute_Name
=> Name_Result
),
5173 Expressions
=> Expressions
(N
)));
5178 Analyze_Attribute_Old_Result
(Legal
, Spec_Id
);
5180 -- The aspect or pragma where attribute 'Result resides should be
5181 -- associated with a subprogram declaration or a body. If this is not
5182 -- the case, then the aspect or pragma is illegal. Return as analysis
5183 -- cannot be carried out.
5189 -- Attribute 'Result is part of a _Postconditions procedure. There is
5190 -- no need to perform the semantic checks below as they were already
5191 -- verified when the attribute was analyzed in its original context.
5192 -- Instead, rewrite the attribute as a reference to formal parameter
5193 -- _Result of the _Postconditions procedure.
5195 if Chars
(Spec_Id
) = Name_uPostconditions
then
5196 Rewrite
(N
, Make_Identifier
(Loc
, Name_uResult
));
5198 -- The type of formal parameter _Result is that of the function
5199 -- encapsulating the _Postconditions procedure. Resolution must
5200 -- be carried out against the function return type.
5202 Analyze_And_Resolve
(N
, Etype
(Scope
(Spec_Id
)));
5204 -- Otherwise attribute 'Result appears in its original context and
5205 -- all semantic checks should be carried out.
5208 -- Verify the legality of the prefix. It must denotes the entity
5209 -- of the related [generic] function.
5211 if Is_Entity_Name
(P
) then
5212 Pref_Id
:= Entity
(P
);
5214 if Ekind_In
(Pref_Id
, E_Function
, E_Generic_Function
) then
5215 if Denote_Same_Function
(Pref_Id
, Spec_Id
) then
5217 -- Correct the prefix of the attribute when the context
5218 -- is a generic function.
5220 if Pref_Id
/= Spec_Id
then
5221 Rewrite
(P
, New_Occurrence_Of
(Spec_Id
, Loc
));
5225 Set_Etype
(N
, Etype
(Spec_Id
));
5227 -- Otherwise the prefix denotes some unrelated function
5230 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5232 ("incorrect prefix for attribute %, expected %", P
);
5235 -- Otherwise the prefix denotes some other form of subprogram
5240 ("attribute % can only appear in postcondition of "
5244 -- Otherwise the prefix is illegal
5247 Error_Msg_Name_2
:= Chars
(Spec_Id
);
5248 Error_Attr
("incorrect prefix for attribute %, expected %", P
);
5257 when Attribute_Range_Length
=>
5259 Check_Discrete_Type
;
5260 Set_Etype
(N
, Universal_Integer
);
5266 when Attribute_Read
=>
5268 Check_Stream_Attribute
(TSS_Stream_Read
);
5269 Set_Etype
(N
, Standard_Void_Type
);
5270 Resolve
(N
, Standard_Void_Type
);
5271 Note_Possible_Modification
(E2
, Sure
=> True);
5277 when Attribute_Ref
=>
5281 if Nkind
(P
) /= N_Expanded_Name
5282 or else not Is_RTE
(P_Type
, RE_Address
)
5284 Error_Attr_P
("prefix of % attribute must be System.Address");
5287 Analyze_And_Resolve
(E1
, Any_Integer
);
5288 Set_Etype
(N
, RTE
(RE_Address
));
5294 when Attribute_Remainder
=>
5295 Check_Floating_Point_Type_2
;
5296 Set_Etype
(N
, P_Base_Type
);
5297 Resolve
(E1
, P_Base_Type
);
5298 Resolve
(E2
, P_Base_Type
);
5300 ---------------------
5301 -- Restriction_Set --
5302 ---------------------
5304 when Attribute_Restriction_Set
=> Restriction_Set
: declare
5307 Unam
: Unit_Name_Type
;
5312 Check_System_Prefix
;
5314 -- No_Dependence case
5316 if Nkind
(E1
) = N_Parameter_Association
then
5317 pragma Assert
(Chars
(Selector_Name
(E1
)) = Name_No_Dependence
);
5318 U
:= Explicit_Actual_Parameter
(E1
);
5320 if not OK_No_Dependence_Unit_Name
(U
) then
5321 Set_Boolean_Result
(N
, False);
5325 -- See if there is an entry already in the table. That's the
5326 -- case in which we can return True.
5328 for J
in No_Dependences
.First
.. No_Dependences
.Last
loop
5329 if Designate_Same_Unit
(U
, No_Dependences
.Table
(J
).Unit
)
5330 and then No_Dependences
.Table
(J
).Warn
= False
5332 Set_Boolean_Result
(N
, True);
5337 -- If not in the No_Dependence table, result is False
5339 Set_Boolean_Result
(N
, False);
5341 -- In this case, we must ensure that the binder will reject any
5342 -- other unit in the partition that sets No_Dependence for this
5343 -- unit. We do that by making an entry in the special table kept
5344 -- for this purpose (if the entry is not there already).
5346 Unam
:= Get_Spec_Name
(Get_Unit_Name
(U
));
5348 for J
in Restriction_Set_Dependences
.First
..
5349 Restriction_Set_Dependences
.Last
5351 if Restriction_Set_Dependences
.Table
(J
) = Unam
then
5356 Restriction_Set_Dependences
.Append
(Unam
);
5358 -- Normal restriction case
5361 if Nkind
(E1
) /= N_Identifier
then
5362 Set_Boolean_Result
(N
, False);
5363 Error_Attr
("attribute % requires restriction identifier", E1
);
5366 R
:= Get_Restriction_Id
(Process_Restriction_Synonyms
(E1
));
5368 if R
= Not_A_Restriction_Id
then
5369 Set_Boolean_Result
(N
, False);
5370 Error_Msg_Node_1
:= E1
;
5371 Error_Attr
("invalid restriction identifier &", E1
);
5373 elsif R
not in Partition_Boolean_Restrictions
then
5374 Set_Boolean_Result
(N
, False);
5375 Error_Msg_Node_1
:= E1
;
5377 ("& is not a boolean partition-wide restriction", E1
);
5380 if Restriction_Active
(R
) then
5381 Set_Boolean_Result
(N
, True);
5383 Check_Restriction
(R
, N
);
5384 Set_Boolean_Result
(N
, False);
5388 end Restriction_Set
;
5394 when Attribute_Round
=>
5396 Check_Decimal_Fixed_Point_Type
;
5397 Set_Etype
(N
, P_Base_Type
);
5399 -- Because the context is universal_real (3.5.10(12)) it is a
5400 -- legal context for a universal fixed expression. This is the
5401 -- only attribute whose functional description involves U_R.
5403 if Etype
(E1
) = Universal_Fixed
then
5405 Conv
: constant Node_Id
:= Make_Type_Conversion
(Loc
,
5406 Subtype_Mark
=> New_Occurrence_Of
(Universal_Real
, Loc
),
5407 Expression
=> Relocate_Node
(E1
));
5415 Resolve
(E1
, Any_Real
);
5421 when Attribute_Rounding
=>
5422 Check_Floating_Point_Type_1
;
5423 Set_Etype
(N
, P_Base_Type
);
5424 Resolve
(E1
, P_Base_Type
);
5430 when Attribute_Safe_Emax
=>
5431 Check_Floating_Point_Type_0
;
5432 Set_Etype
(N
, Universal_Integer
);
5438 when Attribute_Safe_First
=>
5439 Check_Floating_Point_Type_0
;
5440 Set_Etype
(N
, Universal_Real
);
5446 when Attribute_Safe_Large
=>
5449 Set_Etype
(N
, Universal_Real
);
5455 when Attribute_Safe_Last
=>
5456 Check_Floating_Point_Type_0
;
5457 Set_Etype
(N
, Universal_Real
);
5463 when Attribute_Safe_Small
=>
5466 Set_Etype
(N
, Universal_Real
);
5468 --------------------------
5469 -- Scalar_Storage_Order --
5470 --------------------------
5472 when Attribute_Scalar_Storage_Order
=> Scalar_Storage_Order
:
5474 Ent
: Entity_Id
:= Empty
;
5480 if not (Is_Record_Type
(P_Type
) or else Is_Array_Type
(P_Type
)) then
5482 -- In GNAT mode, the attribute applies to generic types as well
5483 -- as composite types, and for non-composite types always returns
5484 -- the default bit order for the target.
5486 if not (GNAT_Mode
and then Is_Generic_Type
(P_Type
))
5487 and then not In_Instance
5490 ("prefix of % attribute must be record or array type");
5492 elsif not Is_Generic_Type
(P_Type
) then
5493 if Bytes_Big_Endian
then
5494 Ent
:= RTE
(RE_High_Order_First
);
5496 Ent
:= RTE
(RE_Low_Order_First
);
5500 elsif Bytes_Big_Endian
xor Reverse_Storage_Order
(P_Type
) then
5501 Ent
:= RTE
(RE_High_Order_First
);
5504 Ent
:= RTE
(RE_Low_Order_First
);
5507 if Present
(Ent
) then
5508 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
5511 Set_Etype
(N
, RTE
(RE_Bit_Order
));
5514 -- Reset incorrect indication of staticness
5516 Set_Is_Static_Expression
(N
, False);
5517 end Scalar_Storage_Order
;
5523 when Attribute_Scale
=>
5525 Check_Decimal_Fixed_Point_Type
;
5526 Set_Etype
(N
, Universal_Integer
);
5532 when Attribute_Scaling
=>
5533 Check_Floating_Point_Type_2
;
5534 Set_Etype
(N
, P_Base_Type
);
5535 Resolve
(E1
, P_Base_Type
);
5541 when Attribute_Signed_Zeros
=>
5542 Check_Floating_Point_Type_0
;
5543 Set_Etype
(N
, Standard_Boolean
);
5549 when Attribute_Size | Attribute_VADS_Size
=> Size
:
5553 -- If prefix is parameterless function call, rewrite and resolve
5556 if Is_Entity_Name
(P
)
5557 and then Ekind
(Entity
(P
)) = E_Function
5561 -- Similar processing for a protected function call
5563 elsif Nkind
(P
) = N_Selected_Component
5564 and then Ekind
(Entity
(Selector_Name
(P
))) = E_Function
5569 if Is_Object_Reference
(P
) then
5570 Check_Object_Reference
(P
);
5572 elsif Is_Entity_Name
(P
)
5573 and then (Is_Type
(Entity
(P
))
5574 or else Ekind
(Entity
(P
)) = E_Enumeration_Literal
)
5578 elsif Nkind
(P
) = N_Type_Conversion
5579 and then not Comes_From_Source
(P
)
5583 -- Some other compilers allow dubious use of X'???'Size
5585 elsif Relaxed_RM_Semantics
5586 and then Nkind
(P
) = N_Attribute_Reference
5591 Error_Attr_P
("invalid prefix for % attribute");
5594 Check_Not_Incomplete_Type
;
5596 Set_Etype
(N
, Universal_Integer
);
5603 when Attribute_Small
=>
5606 Set_Etype
(N
, Universal_Real
);
5612 when Attribute_Storage_Pool |
5613 Attribute_Simple_Storage_Pool
=> Storage_Pool
:
5617 if Is_Access_Type
(P_Type
) then
5618 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5620 ("cannot use % attribute for access-to-subprogram type");
5623 -- Set appropriate entity
5625 if Present
(Associated_Storage_Pool
(Root_Type
(P_Type
))) then
5626 Set_Entity
(N
, Associated_Storage_Pool
(Root_Type
(P_Type
)));
5628 Set_Entity
(N
, RTE
(RE_Global_Pool_Object
));
5631 if Attr_Id
= Attribute_Storage_Pool
then
5632 if Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5633 Name_Simple_Storage_Pool_Type
))
5635 Error_Msg_Name_1
:= Aname
;
5636 Error_Msg_Warn
:= SPARK_Mode
/= On
;
5637 Error_Msg_N
("cannot use % attribute for type with simple "
5638 & "storage pool<<", N
);
5639 Error_Msg_N
("\Program_Error [<<", N
);
5642 (N
, Make_Raise_Program_Error
5643 (Sloc
(N
), Reason
=> PE_Explicit_Raise
));
5646 Set_Etype
(N
, Class_Wide_Type
(RTE
(RE_Root_Storage_Pool
)));
5648 -- In the Simple_Storage_Pool case, verify that the pool entity is
5649 -- actually of a simple storage pool type, and set the attribute's
5650 -- type to the pool object's type.
5653 if not Present
(Get_Rep_Pragma
(Etype
(Entity
(N
)),
5654 Name_Simple_Storage_Pool_Type
))
5657 ("cannot use % attribute for type without simple " &
5661 Set_Etype
(N
, Etype
(Entity
(N
)));
5664 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5665 -- Storage_Pool since this attribute is not defined for such
5666 -- types (RM E.2.3(22)).
5668 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5671 Error_Attr_P
("prefix of % attribute must be access type");
5679 when Attribute_Storage_Size
=> Storage_Size
:
5683 if Is_Task_Type
(P_Type
) then
5684 Set_Etype
(N
, Universal_Integer
);
5686 -- Use with tasks is an obsolescent feature
5688 Check_Restriction
(No_Obsolescent_Features
, P
);
5690 elsif Is_Access_Type
(P_Type
) then
5691 if Ekind
(P_Type
) = E_Access_Subprogram_Type
then
5693 ("cannot use % attribute for access-to-subprogram type");
5696 if Is_Entity_Name
(P
)
5697 and then Is_Type
(Entity
(P
))
5700 Set_Etype
(N
, Universal_Integer
);
5702 -- Validate_Remote_Access_To_Class_Wide_Type for attribute
5703 -- Storage_Size since this attribute is not defined for
5704 -- such types (RM E.2.3(22)).
5706 Validate_Remote_Access_To_Class_Wide_Type
(N
);
5708 -- The prefix is allowed to be an implicit dereference of an
5709 -- access value designating a task.
5713 Set_Etype
(N
, Universal_Integer
);
5717 Error_Attr_P
("prefix of % attribute must be access or task type");
5725 when Attribute_Storage_Unit
=>
5726 Standard_Attribute
(Ttypes
.System_Storage_Unit
);
5732 when Attribute_Stream_Size
=>
5736 if Is_Entity_Name
(P
)
5737 and then Is_Elementary_Type
(Entity
(P
))
5739 Set_Etype
(N
, Universal_Integer
);
5741 Error_Attr_P
("invalid prefix for % attribute");
5748 when Attribute_Stub_Type
=>
5752 if Is_Remote_Access_To_Class_Wide_Type
(Base_Type
(P_Type
)) then
5754 -- For a real RACW [sub]type, use corresponding stub type
5756 if not Is_Generic_Type
(P_Type
) then
5759 (Corresponding_Stub_Type
(Base_Type
(P_Type
)), Loc
));
5761 -- For a generic type (that has been marked as an RACW using the
5762 -- Remote_Access_Type aspect or pragma), use a generic RACW stub
5763 -- type. Note that if the actual is not a remote access type, the
5764 -- instantiation will fail.
5767 -- Note: we go to the underlying type here because the view
5768 -- returned by RTE (RE_RACW_Stub_Type) might be incomplete.
5772 (Underlying_Type
(RTE
(RE_RACW_Stub_Type
)), Loc
));
5777 ("prefix of% attribute must be remote access to classwide");
5784 when Attribute_Succ
=>
5788 if Is_Real_Type
(P_Type
) or else Is_Boolean_Type
(P_Type
) then
5789 Error_Msg_Name_1
:= Aname
;
5790 Error_Msg_Name_2
:= Chars
(P_Type
);
5791 Check_SPARK_05_Restriction
5792 ("attribute% is not allowed for type%", P
);
5795 Resolve
(E1
, P_Base_Type
);
5796 Set_Etype
(N
, P_Base_Type
);
5798 -- Since Pred works on the base type, we normally do no check for the
5799 -- floating-point case, since the base type is unconstrained. But we
5800 -- make an exception in Check_Float_Overflow mode.
5802 if Is_Floating_Point_Type
(P_Type
) then
5803 if not Range_Checks_Suppressed
(P_Base_Type
) then
5804 Set_Do_Range_Check
(E1
);
5807 -- If not modular type, test for overflow check required
5810 if not Is_Modular_Integer_Type
(P_Type
)
5811 and then not Range_Checks_Suppressed
(P_Base_Type
)
5813 Enable_Range_Check
(E1
);
5817 --------------------------------
5818 -- System_Allocator_Alignment --
5819 --------------------------------
5821 when Attribute_System_Allocator_Alignment
=>
5822 Standard_Attribute
(Ttypes
.System_Allocator_Alignment
);
5828 when Attribute_Tag
=> Tag
:
5833 if not Is_Tagged_Type
(P_Type
) then
5834 Error_Attr_P
("prefix of % attribute must be tagged");
5836 -- Next test does not apply to generated code why not, and what does
5837 -- the illegal reference mean???
5839 elsif Is_Object_Reference
(P
)
5840 and then not Is_Class_Wide_Type
(P_Type
)
5841 and then Comes_From_Source
(N
)
5844 ("% attribute can only be applied to objects " &
5845 "of class - wide type");
5848 -- The prefix cannot be an incomplete type. However, references to
5849 -- 'Tag can be generated when expanding interface conversions, and
5852 if Comes_From_Source
(N
) then
5853 Check_Not_Incomplete_Type
;
5856 -- Set appropriate type
5858 Set_Etype
(N
, RTE
(RE_Tag
));
5865 when Attribute_Target_Name
=> Target_Name
: declare
5866 TN
: constant String := Sdefault
.Target_Name
.all;
5870 Check_Standard_Prefix
;
5874 if TN
(TL
) = '/' or else TN
(TL
) = '\' then
5879 Make_String_Literal
(Loc
,
5880 Strval
=> TN
(TN
'First .. TL
)));
5881 Analyze_And_Resolve
(N
, Standard_String
);
5882 Set_Is_Static_Expression
(N
, True);
5889 when Attribute_Terminated
=>
5891 Set_Etype
(N
, Standard_Boolean
);
5898 when Attribute_To_Address
=> To_Address
: declare
5904 Check_System_Prefix
;
5906 Generate_Reference
(RTE
(RE_Address
), P
);
5907 Analyze_And_Resolve
(E1
, Any_Integer
);
5908 Set_Etype
(N
, RTE
(RE_Address
));
5910 if Is_Static_Expression
(E1
) then
5911 Set_Is_Static_Expression
(N
, True);
5914 -- OK static expression case, check range and set appropriate type
5916 if Is_OK_Static_Expression
(E1
) then
5917 Val
:= Expr_Value
(E1
);
5919 if Val
< -(2 ** UI_From_Int
(Standard
'Address_Size - 1))
5921 Val
> 2 ** UI_From_Int
(Standard
'Address_Size) - 1
5923 Error_Attr
("address value out of range for % attribute", E1
);
5926 -- In most cases the expression is a numeric literal or some other
5927 -- address expression, but if it is a declared constant it may be
5928 -- of a compatible type that must be left on the node.
5930 if Is_Entity_Name
(E1
) then
5933 -- Set type to universal integer if negative
5936 Set_Etype
(E1
, Universal_Integer
);
5938 -- Otherwise set type to Unsigned_64 to accomodate max values
5941 Set_Etype
(E1
, Standard_Unsigned_64
);
5945 Set_Is_Static_Expression
(N
, True);
5952 when Attribute_To_Any
=>
5954 Check_PolyORB_Attribute
;
5955 Set_Etype
(N
, RTE
(RE_Any
));
5961 when Attribute_Truncation
=>
5962 Check_Floating_Point_Type_1
;
5963 Resolve
(E1
, P_Base_Type
);
5964 Set_Etype
(N
, P_Base_Type
);
5970 when Attribute_Type_Class
=>
5973 Check_Not_Incomplete_Type
;
5974 Set_Etype
(N
, RTE
(RE_Type_Class
));
5980 when Attribute_TypeCode
=>
5982 Check_PolyORB_Attribute
;
5983 Set_Etype
(N
, RTE
(RE_TypeCode
));
5989 when Attribute_Type_Key
=>
5993 -- This processing belongs in Eval_Attribute ???
5996 function Type_Key
return String_Id
;
5997 -- A very preliminary implementation. For now, a signature
5998 -- consists of only the type name. This is clearly incomplete
5999 -- (e.g., adding a new field to a record type should change the
6000 -- type's Type_Key attribute).
6006 function Type_Key
return String_Id
is
6007 Full_Name
: constant String_Id
:=
6008 Fully_Qualified_Name_String
(Entity
(P
));
6011 -- Copy all characters in Full_Name but the trailing NUL
6014 for J
in 1 .. String_Length
(Full_Name
) - 1 loop
6015 Store_String_Char
(Get_String_Char
(Full_Name
, Int
(J
)));
6018 Store_String_Chars
("'Type_Key");
6023 Rewrite
(N
, Make_String_Literal
(Loc
, Type_Key
));
6026 Analyze_And_Resolve
(N
, Standard_String
);
6028 -----------------------
6029 -- Unbiased_Rounding --
6030 -----------------------
6032 when Attribute_Unbiased_Rounding
=>
6033 Check_Floating_Point_Type_1
;
6034 Set_Etype
(N
, P_Base_Type
);
6035 Resolve
(E1
, P_Base_Type
);
6037 ----------------------
6038 -- Unchecked_Access --
6039 ----------------------
6041 when Attribute_Unchecked_Access
=>
6042 if Comes_From_Source
(N
) then
6043 Check_Restriction
(No_Unchecked_Access
, N
);
6046 Analyze_Access_Attribute
;
6047 Check_Not_Incomplete_Type
;
6049 -------------------------
6050 -- Unconstrained_Array --
6051 -------------------------
6053 when Attribute_Unconstrained_Array
=>
6056 Check_Not_Incomplete_Type
;
6057 Set_Etype
(N
, Standard_Boolean
);
6058 Set_Is_Static_Expression
(N
, True);
6060 ------------------------------
6061 -- Universal_Literal_String --
6062 ------------------------------
6064 -- This is a GNAT specific attribute whose prefix must be a named
6065 -- number where the expression is either a single numeric literal,
6066 -- or a numeric literal immediately preceded by a minus sign. The
6067 -- result is equivalent to a string literal containing the text of
6068 -- the literal as it appeared in the source program with a possible
6069 -- leading minus sign.
6071 when Attribute_Universal_Literal_String
=> Universal_Literal_String
:
6075 if not Is_Entity_Name
(P
)
6076 or else Ekind
(Entity
(P
)) not in Named_Kind
6078 Error_Attr_P
("prefix for % attribute must be named number");
6085 Src
: Source_Buffer_Ptr
;
6088 Expr
:= Original_Node
(Expression
(Parent
(Entity
(P
))));
6090 if Nkind
(Expr
) = N_Op_Minus
then
6092 Expr
:= Original_Node
(Right_Opnd
(Expr
));
6097 if not Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
) then
6099 ("named number for % attribute must be simple literal", N
);
6102 -- Build string literal corresponding to source literal text
6107 Store_String_Char
(Get_Char_Code
('-'));
6111 Src
:= Source_Text
(Get_Source_File_Index
(S
));
6113 while Src
(S
) /= ';' and then Src
(S
) /= ' ' loop
6114 Store_String_Char
(Get_Char_Code
(Src
(S
)));
6118 -- Now we rewrite the attribute with the string literal
6121 Make_String_Literal
(Loc
, End_String
));
6123 Set_Is_Static_Expression
(N
, True);
6126 end Universal_Literal_String
;
6128 -------------------------
6129 -- Unrestricted_Access --
6130 -------------------------
6132 -- This is a GNAT specific attribute which is like Access except that
6133 -- all scope checks and checks for aliased views are omitted. It is
6134 -- documented as being equivalent to the use of the Address attribute
6135 -- followed by an unchecked conversion to the target access type.
6137 when Attribute_Unrestricted_Access
=>
6139 -- If from source, deal with relevant restrictions
6141 if Comes_From_Source
(N
) then
6142 Check_Restriction
(No_Unchecked_Access
, N
);
6144 if Nkind
(P
) in N_Has_Entity
6145 and then Present
(Entity
(P
))
6146 and then Is_Object
(Entity
(P
))
6148 Check_Restriction
(No_Implicit_Aliasing
, N
);
6152 if Is_Entity_Name
(P
) then
6153 Set_Address_Taken
(Entity
(P
));
6156 -- It might seem reasonable to call Address_Checks here to apply the
6157 -- same set of semantic checks that we enforce for 'Address (after
6158 -- all we document Unrestricted_Access as being equivalent to the
6159 -- use of Address followed by an Unchecked_Conversion). However, if
6160 -- we do enable these checks, we get multiple failures in both the
6161 -- compiler run-time and in our regression test suite, so we leave
6162 -- out these checks for now. To be investigated further some time???
6166 -- Now complete analysis using common access processing
6168 Analyze_Access_Attribute
;
6174 when Attribute_Update
=> Update
: declare
6175 Common_Typ
: Entity_Id
;
6176 -- The common type of a multiple component update for a record
6178 Comps
: Elist_Id
:= No_Elist
;
6179 -- A list used in the resolution of a record update. It contains the
6180 -- entities of all record components processed so far.
6182 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
);
6183 -- Analyze and resolve array_component_association Assoc against the
6184 -- index of array type P_Type.
6186 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
);
6187 -- Analyze and resolve record_component_association Comp against
6188 -- record type P_Type.
6190 ------------------------------------
6191 -- Analyze_Array_Component_Update --
6192 ------------------------------------
6194 procedure Analyze_Array_Component_Update
(Assoc
: Node_Id
) is
6198 Index_Typ
: Entity_Id
;
6202 -- The current association contains a sequence of indexes denoting
6203 -- an element of a multidimensional array:
6205 -- (Index_1, ..., Index_N)
6207 -- Examine each individual index and resolve it against the proper
6208 -- index type of the array.
6210 if Nkind
(First
(Choices
(Assoc
))) = N_Aggregate
then
6211 Expr
:= First
(Choices
(Assoc
));
6212 while Present
(Expr
) loop
6214 -- The use of others is illegal (SPARK RM 4.4.1(12))
6216 if Nkind
(Expr
) = N_Others_Choice
then
6218 ("others choice not allowed in attribute %", Expr
);
6220 -- Otherwise analyze and resolve all indexes
6223 Index
:= First
(Expressions
(Expr
));
6224 Index_Typ
:= First_Index
(P_Type
);
6225 while Present
(Index
) and then Present
(Index_Typ
) loop
6226 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6228 Next_Index
(Index_Typ
);
6231 -- Detect a case where the association either lacks an
6232 -- index or contains an extra index.
6234 if Present
(Index
) or else Present
(Index_Typ
) then
6236 ("dimension mismatch in index list", Assoc
);
6243 -- The current association denotes either a single component or a
6244 -- range of components of a one dimensional array:
6248 -- Resolve the index or its high and low bounds (if range) against
6249 -- the proper index type of the array.
6252 Index
:= First
(Choices
(Assoc
));
6253 Index_Typ
:= First_Index
(P_Type
);
6255 if Present
(Next_Index
(Index_Typ
)) then
6256 Error_Msg_N
("too few subscripts in array reference", Assoc
);
6259 while Present
(Index
) loop
6261 -- The use of others is illegal (SPARK RM 4.4.1(12))
6263 if Nkind
(Index
) = N_Others_Choice
then
6265 ("others choice not allowed in attribute %", Index
);
6267 -- The index denotes a range of elements
6269 elsif Nkind
(Index
) = N_Range
then
6270 Low
:= Low_Bound
(Index
);
6271 High
:= High_Bound
(Index
);
6273 Analyze_And_Resolve
(Low
, Etype
(Index_Typ
));
6274 Analyze_And_Resolve
(High
, Etype
(Index_Typ
));
6276 -- Add a range check to ensure that the bounds of the
6277 -- range are within the index type when this cannot be
6278 -- determined statically.
6280 if not Is_OK_Static_Expression
(Low
) then
6281 Set_Do_Range_Check
(Low
);
6284 if not Is_OK_Static_Expression
(High
) then
6285 Set_Do_Range_Check
(High
);
6288 -- Otherwise the index denotes a single element
6291 Analyze_And_Resolve
(Index
, Etype
(Index_Typ
));
6293 -- Add a range check to ensure that the index is within
6294 -- the index type when it is not possible to determine
6297 if not Is_OK_Static_Expression
(Index
) then
6298 Set_Do_Range_Check
(Index
);
6305 end Analyze_Array_Component_Update
;
6307 -------------------------------------
6308 -- Analyze_Record_Component_Update --
6309 -------------------------------------
6311 procedure Analyze_Record_Component_Update
(Comp
: Node_Id
) is
6312 Comp_Name
: constant Name_Id
:= Chars
(Comp
);
6313 Base_Typ
: Entity_Id
;
6314 Comp_Or_Discr
: Entity_Id
;
6317 -- Find the discriminant or component whose name corresponds to
6318 -- Comp. A simple character comparison is sufficient because all
6319 -- visible names within a record type are unique.
6321 Comp_Or_Discr
:= First_Entity
(P_Type
);
6322 while Present
(Comp_Or_Discr
) loop
6323 if Chars
(Comp_Or_Discr
) = Comp_Name
then
6325 -- Decorate the component reference by setting its entity
6326 -- and type for resolution purposes.
6328 Set_Entity
(Comp
, Comp_Or_Discr
);
6329 Set_Etype
(Comp
, Etype
(Comp_Or_Discr
));
6333 Comp_Or_Discr
:= Next_Entity
(Comp_Or_Discr
);
6336 -- Diagnose an illegal reference
6338 if Present
(Comp_Or_Discr
) then
6339 if Ekind
(Comp_Or_Discr
) = E_Discriminant
then
6341 ("attribute % may not modify record discriminants", Comp
);
6343 else pragma Assert
(Ekind
(Comp_Or_Discr
) = E_Component
);
6344 if Contains
(Comps
, Comp_Or_Discr
) then
6345 Error_Msg_N
("component & already updated", Comp
);
6347 -- Mark this component as processed
6350 Append_New_Elmt
(Comp_Or_Discr
, Comps
);
6354 -- The update aggregate mentions an entity that does not belong to
6358 Error_Msg_N
("& is not a component of aggregate subtype", Comp
);
6361 -- Verify the consistency of types when the current component is
6362 -- part of a miltiple component update.
6364 -- Comp_1, ..., Comp_N => <value>
6366 if Present
(Etype
(Comp
)) then
6367 Base_Typ
:= Base_Type
(Etype
(Comp
));
6369 -- Save the type of the first component reference as the
6370 -- remaning references (if any) must resolve to this type.
6372 if No
(Common_Typ
) then
6373 Common_Typ
:= Base_Typ
;
6375 elsif Base_Typ
/= Common_Typ
then
6377 ("components in choice list must have same type", Comp
);
6380 end Analyze_Record_Component_Update
;
6387 -- Start of processing for Update
6392 if not Is_Object_Reference
(P
) then
6393 Error_Attr_P
("prefix of attribute % must denote an object");
6395 elsif not Is_Array_Type
(P_Type
)
6396 and then not Is_Record_Type
(P_Type
)
6398 Error_Attr_P
("prefix of attribute % must be a record or array");
6400 elsif Is_Limited_View
(P_Type
) then
6401 Error_Attr
("prefix of attribute % cannot be limited", N
);
6403 elsif Nkind
(E1
) /= N_Aggregate
then
6404 Error_Attr
("attribute % requires component association list", N
);
6407 -- Inspect the update aggregate, looking at all the associations and
6408 -- choices. Perform the following checks:
6410 -- 1) Legality of "others" in all cases
6411 -- 2) Legality of <>
6412 -- 3) Component legality for arrays
6413 -- 4) Component legality for records
6415 -- The remaining checks are performed on the expanded attribute
6417 Assoc
:= First
(Component_Associations
(E1
));
6418 while Present
(Assoc
) loop
6420 -- The use of <> is illegal (SPARK RM 4.4.1(1))
6422 if Box_Present
(Assoc
) then
6424 ("default initialization not allowed in attribute %", Assoc
);
6426 -- Otherwise process the association
6429 Analyze
(Expression
(Assoc
));
6431 if Is_Array_Type
(P_Type
) then
6432 Analyze_Array_Component_Update
(Assoc
);
6434 elsif Is_Record_Type
(P_Type
) then
6436 -- Reset the common type used in a multiple component update
6437 -- as we are processing the contents of a new association.
6439 Common_Typ
:= Empty
;
6441 Comp
:= First
(Choices
(Assoc
));
6442 while Present
(Comp
) loop
6443 if Nkind
(Comp
) = N_Identifier
then
6444 Analyze_Record_Component_Update
(Comp
);
6446 -- The use of others is illegal (SPARK RM 4.4.1(5))
6448 elsif Nkind
(Comp
) = N_Others_Choice
then
6450 ("others choice not allowed in attribute %", Comp
);
6452 -- The name of a record component cannot appear in any
6457 ("name should be identifier or OTHERS", Comp
);
6468 -- The type of attribute 'Update is that of the prefix
6470 Set_Etype
(N
, P_Type
);
6472 Sem_Warn
.Warn_On_Suspicious_Update
(N
);
6479 when Attribute_Val
=> Val
: declare
6482 Check_Discrete_Type
;
6484 if Is_Boolean_Type
(P_Type
) then
6485 Error_Msg_Name_1
:= Aname
;
6486 Error_Msg_Name_2
:= Chars
(P_Type
);
6487 Check_SPARK_05_Restriction
6488 ("attribute% is not allowed for type%", P
);
6491 Resolve
(E1
, Any_Integer
);
6492 Set_Etype
(N
, P_Base_Type
);
6494 -- Note, we need a range check in general, but we wait for the
6495 -- Resolve call to do this, since we want to let Eval_Attribute
6496 -- have a chance to find an static illegality first.
6503 when Attribute_Valid
=>
6506 -- Ignore check for object if we have a 'Valid reference generated
6507 -- by the expanded code, since in some cases valid checks can occur
6508 -- on items that are names, but are not objects (e.g. attributes).
6510 if Comes_From_Source
(N
) then
6511 Check_Object_Reference
(P
);
6514 if not Is_Scalar_Type
(P_Type
) then
6515 Error_Attr_P
("object for % attribute must be of scalar type");
6518 -- If the attribute appears within the subtype's own predicate
6519 -- function, then issue a warning that this will cause infinite
6523 Pred_Func
: constant Entity_Id
:= Predicate_Function
(P_Type
);
6526 if Present
(Pred_Func
) and then Current_Scope
= Pred_Func
then
6528 ("attribute Valid requires a predicate check??", N
);
6529 Error_Msg_N
("\and will result in infinite recursion??", N
);
6533 Set_Etype
(N
, Standard_Boolean
);
6539 when Attribute_Valid_Scalars
=>
6541 Check_Object_Reference
(P
);
6542 Set_Etype
(N
, Standard_Boolean
);
6544 -- Following checks are only for source types
6546 if Comes_From_Source
(N
) then
6547 if not Scalar_Part_Present
(P_Type
) then
6549 ("??attribute % always True, no scalars to check");
6552 -- Not allowed for unchecked union type
6554 if Has_Unchecked_Union
(P_Type
) then
6556 ("attribute % not allowed for Unchecked_Union type");
6564 when Attribute_Value
=> Value
:
6566 Check_SPARK_05_Restriction_On_Attribute
;
6570 -- Case of enumeration type
6572 -- When an enumeration type appears in an attribute reference, all
6573 -- literals of the type are marked as referenced. This must only be
6574 -- done if the attribute reference appears in the current source.
6575 -- Otherwise the information on references may differ between a
6576 -- normal compilation and one that performs inlining.
6578 if Is_Enumeration_Type
(P_Type
)
6579 and then In_Extended_Main_Code_Unit
(N
)
6581 Check_Restriction
(No_Enumeration_Maps
, N
);
6583 -- Mark all enumeration literals as referenced, since the use of
6584 -- the Value attribute can implicitly reference any of the
6585 -- literals of the enumeration base type.
6588 Ent
: Entity_Id
:= First_Literal
(P_Base_Type
);
6590 while Present
(Ent
) loop
6591 Set_Referenced
(Ent
);
6597 -- Set Etype before resolving expression because expansion of
6598 -- expression may require enclosing type. Note that the type
6599 -- returned by 'Value is the base type of the prefix type.
6601 Set_Etype
(N
, P_Base_Type
);
6602 Validate_Non_Static_Attribute_Function_Call
;
6604 -- Check restriction No_Fixed_IO
6606 if Restriction_Check_Required
(No_Fixed_IO
)
6607 and then Is_Fixed_Point_Type
(P_Type
)
6609 Check_Restriction
(No_Fixed_IO
, P
);
6617 when Attribute_Value_Size
=>
6620 Check_Not_Incomplete_Type
;
6621 Set_Etype
(N
, Universal_Integer
);
6627 when Attribute_Version
=>
6630 Set_Etype
(N
, RTE
(RE_Version_String
));
6636 when Attribute_Wchar_T_Size
=>
6637 Standard_Attribute
(Interfaces_Wchar_T_Size
);
6643 when Attribute_Wide_Image
=> Wide_Image
:
6645 Check_SPARK_05_Restriction_On_Attribute
;
6647 Set_Etype
(N
, Standard_Wide_String
);
6649 Resolve
(E1
, P_Base_Type
);
6650 Validate_Non_Static_Attribute_Function_Call
;
6652 -- Check restriction No_Fixed_IO
6654 if Restriction_Check_Required
(No_Fixed_IO
)
6655 and then Is_Fixed_Point_Type
(P_Type
)
6657 Check_Restriction
(No_Fixed_IO
, P
);
6661 ---------------------
6662 -- Wide_Wide_Image --
6663 ---------------------
6665 when Attribute_Wide_Wide_Image
=> Wide_Wide_Image
:
6668 Set_Etype
(N
, Standard_Wide_Wide_String
);
6670 Resolve
(E1
, P_Base_Type
);
6671 Validate_Non_Static_Attribute_Function_Call
;
6673 -- Check restriction No_Fixed_IO
6675 if Restriction_Check_Required
(No_Fixed_IO
)
6676 and then Is_Fixed_Point_Type
(P_Type
)
6678 Check_Restriction
(No_Fixed_IO
, P
);
6680 end Wide_Wide_Image
;
6686 when Attribute_Wide_Value
=> Wide_Value
:
6688 Check_SPARK_05_Restriction_On_Attribute
;
6692 -- Set Etype before resolving expression because expansion
6693 -- of expression may require enclosing type.
6695 Set_Etype
(N
, P_Type
);
6696 Validate_Non_Static_Attribute_Function_Call
;
6698 -- Check restriction No_Fixed_IO
6700 if Restriction_Check_Required
(No_Fixed_IO
)
6701 and then Is_Fixed_Point_Type
(P_Type
)
6703 Check_Restriction
(No_Fixed_IO
, P
);
6707 ---------------------
6708 -- Wide_Wide_Value --
6709 ---------------------
6711 when Attribute_Wide_Wide_Value
=> Wide_Wide_Value
:
6716 -- Set Etype before resolving expression because expansion
6717 -- of expression may require enclosing type.
6719 Set_Etype
(N
, P_Type
);
6720 Validate_Non_Static_Attribute_Function_Call
;
6722 -- Check restriction No_Fixed_IO
6724 if Restriction_Check_Required
(No_Fixed_IO
)
6725 and then Is_Fixed_Point_Type
(P_Type
)
6727 Check_Restriction
(No_Fixed_IO
, P
);
6729 end Wide_Wide_Value
;
6731 ---------------------
6732 -- Wide_Wide_Width --
6733 ---------------------
6735 when Attribute_Wide_Wide_Width
=>
6738 Set_Etype
(N
, Universal_Integer
);
6744 when Attribute_Wide_Width
=>
6745 Check_SPARK_05_Restriction_On_Attribute
;
6748 Set_Etype
(N
, Universal_Integer
);
6754 when Attribute_Width
=>
6755 Check_SPARK_05_Restriction_On_Attribute
;
6758 Set_Etype
(N
, Universal_Integer
);
6764 when Attribute_Word_Size
=>
6765 Standard_Attribute
(System_Word_Size
);
6771 when Attribute_Write
=>
6773 Check_Stream_Attribute
(TSS_Stream_Write
);
6774 Set_Etype
(N
, Standard_Void_Type
);
6775 Resolve
(N
, Standard_Void_Type
);
6779 -- All errors raise Bad_Attribute, so that we get out before any further
6780 -- damage occurs when an error is detected (for example, if we check for
6781 -- one attribute expression, and the check succeeds, we want to be able
6782 -- to proceed securely assuming that an expression is in fact present.
6784 -- Note: we set the attribute analyzed in this case to prevent any
6785 -- attempt at reanalysis which could generate spurious error msgs.
6788 when Bad_Attribute
=>
6790 Set_Etype
(N
, Any_Type
);
6792 end Analyze_Attribute
;
6794 --------------------
6795 -- Eval_Attribute --
6796 --------------------
6798 procedure Eval_Attribute
(N
: Node_Id
) is
6799 Loc
: constant Source_Ptr
:= Sloc
(N
);
6800 Aname
: constant Name_Id
:= Attribute_Name
(N
);
6801 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
6802 P
: constant Node_Id
:= Prefix
(N
);
6804 C_Type
: constant Entity_Id
:= Etype
(N
);
6805 -- The type imposed by the context
6808 -- First expression, or Empty if none
6811 -- Second expression, or Empty if none
6813 P_Entity
: Entity_Id
;
6814 -- Entity denoted by prefix
6817 -- The type of the prefix
6819 P_Base_Type
: Entity_Id
;
6820 -- The base type of the prefix type
6822 P_Root_Type
: Entity_Id
;
6823 -- The root type of the prefix type
6826 -- True if the result is Static. This is set by the general processing
6827 -- to true if the prefix is static, and all expressions are static. It
6828 -- can be reset as processing continues for particular attributes. This
6829 -- flag can still be True if the reference raises a constraint error.
6830 -- Is_Static_Expression (N) is set to follow this value as it is set
6831 -- and we could always reference this, but it is convenient to have a
6832 -- simple short name to use, since it is frequently referenced.
6834 Lo_Bound
, Hi_Bound
: Node_Id
;
6835 -- Expressions for low and high bounds of type or array index referenced
6836 -- by First, Last, or Length attribute for array, set by Set_Bounds.
6839 -- Constraint error node used if we have an attribute reference has
6840 -- an argument that raises a constraint error. In this case we replace
6841 -- the attribute with a raise constraint_error node. This is important
6842 -- processing, since otherwise gigi might see an attribute which it is
6843 -- unprepared to deal with.
6845 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
);
6846 -- If Bound is a reference to a discriminant of a task or protected type
6847 -- occurring within the object's body, rewrite attribute reference into
6848 -- a reference to the corresponding discriminal. Use for the expansion
6849 -- of checks against bounds of entry family index subtypes.
6851 procedure Check_Expressions
;
6852 -- In case where the attribute is not foldable, the expressions, if
6853 -- any, of the attribute, are in a non-static context. This procedure
6854 -- performs the required additional checks.
6856 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean;
6857 -- Determines if the given type has compile time known bounds. Note
6858 -- that we enter the case statement even in cases where the prefix
6859 -- type does NOT have known bounds, so it is important to guard any
6860 -- attempt to evaluate both bounds with a call to this function.
6862 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
);
6863 -- This procedure is called when the attribute N has a non-static
6864 -- but compile time known value given by Val. It includes the
6865 -- necessary checks for out of range values.
6867 function Fore_Value
return Nat
;
6868 -- Computes the Fore value for the current attribute prefix, which is
6869 -- known to be a static fixed-point type. Used by Fore and Width.
6871 function Mantissa
return Uint
;
6872 -- Returns the Mantissa value for the prefix type
6874 procedure Set_Bounds
;
6875 -- Used for First, Last and Length attributes applied to an array or
6876 -- array subtype. Sets the variables Lo_Bound and Hi_Bound to the low
6877 -- and high bound expressions for the index referenced by the attribute
6878 -- designator (i.e. the first index if no expression is present, and the
6879 -- N'th index if the value N is present as an expression). Also used for
6880 -- First and Last of scalar types and for First_Valid and Last_Valid.
6881 -- Static is reset to False if the type or index type is not statically
6884 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean;
6885 -- Verify that the prefix of a potentially static array attribute
6886 -- satisfies the conditions of 4.9 (14).
6888 -----------------------------------
6889 -- Check_Concurrent_Discriminant --
6890 -----------------------------------
6892 procedure Check_Concurrent_Discriminant
(Bound
: Node_Id
) is
6894 -- The concurrent (task or protected) type
6897 if Nkind
(Bound
) = N_Identifier
6898 and then Ekind
(Entity
(Bound
)) = E_Discriminant
6899 and then Is_Concurrent_Record_Type
(Scope
(Entity
(Bound
)))
6901 Tsk
:= Corresponding_Concurrent_Type
(Scope
(Entity
(Bound
)));
6903 if In_Open_Scopes
(Tsk
) and then Has_Completion
(Tsk
) then
6905 -- Find discriminant of original concurrent type, and use
6906 -- its current discriminal, which is the renaming within
6907 -- the task/protected body.
6911 (Find_Body_Discriminal
(Entity
(Bound
)), Loc
));
6914 end Check_Concurrent_Discriminant
;
6916 -----------------------
6917 -- Check_Expressions --
6918 -----------------------
6920 procedure Check_Expressions
is
6924 while Present
(E
) loop
6925 Check_Non_Static_Context
(E
);
6928 end Check_Expressions
;
6930 ----------------------------------
6931 -- Compile_Time_Known_Attribute --
6932 ----------------------------------
6934 procedure Compile_Time_Known_Attribute
(N
: Node_Id
; Val
: Uint
) is
6935 T
: constant Entity_Id
:= Etype
(N
);
6938 Fold_Uint
(N
, Val
, False);
6940 -- Check that result is in bounds of the type if it is static
6942 if Is_In_Range
(N
, T
, Assume_Valid
=> False) then
6945 elsif Is_Out_Of_Range
(N
, T
) then
6946 Apply_Compile_Time_Constraint_Error
6947 (N
, "value not in range of}??", CE_Range_Check_Failed
);
6949 elsif not Range_Checks_Suppressed
(T
) then
6950 Enable_Range_Check
(N
);
6953 Set_Do_Range_Check
(N
, False);
6955 end Compile_Time_Known_Attribute
;
6957 -------------------------------
6958 -- Compile_Time_Known_Bounds --
6959 -------------------------------
6961 function Compile_Time_Known_Bounds
(Typ
: Entity_Id
) return Boolean is
6964 Compile_Time_Known_Value
(Type_Low_Bound
(Typ
))
6966 Compile_Time_Known_Value
(Type_High_Bound
(Typ
));
6967 end Compile_Time_Known_Bounds
;
6973 -- Note that the Fore calculation is based on the actual values
6974 -- of the bounds, and does not take into account possible rounding.
6976 function Fore_Value
return Nat
is
6977 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
6978 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
6979 Small
: constant Ureal
:= Small_Value
(P_Type
);
6980 Lo_Real
: constant Ureal
:= Lo
* Small
;
6981 Hi_Real
: constant Ureal
:= Hi
* Small
;
6986 -- Bounds are given in terms of small units, so first compute
6987 -- proper values as reals.
6989 T
:= UR_Max
(abs Lo_Real
, abs Hi_Real
);
6992 -- Loop to compute proper value if more than one digit required
6994 while T
>= Ureal_10
loop
7006 -- Table of mantissa values accessed by function Computed using
7009 -- T'Mantissa = integer next above (D * log(10)/log(2)) + 1)
7011 -- where D is T'Digits (RM83 3.5.7)
7013 Mantissa_Value
: constant array (Nat
range 1 .. 40) of Nat
:= (
7055 function Mantissa
return Uint
is
7058 UI_From_Int
(Mantissa_Value
(UI_To_Int
(Digits_Value
(P_Type
))));
7065 procedure Set_Bounds
is
7071 -- For a string literal subtype, we have to construct the bounds.
7072 -- Valid Ada code never applies attributes to string literals, but
7073 -- it is convenient to allow the expander to generate attribute
7074 -- references of this type (e.g. First and Last applied to a string
7077 -- Note that the whole point of the E_String_Literal_Subtype is to
7078 -- avoid this construction of bounds, but the cases in which we
7079 -- have to materialize them are rare enough that we don't worry.
7081 -- The low bound is simply the low bound of the base type. The
7082 -- high bound is computed from the length of the string and this
7085 if Ekind
(P_Type
) = E_String_Literal_Subtype
then
7086 Ityp
:= Etype
(First_Index
(Base_Type
(P_Type
)));
7087 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7090 Make_Integer_Literal
(Sloc
(P
),
7092 Expr_Value
(Lo_Bound
) + String_Literal_Length
(P_Type
) - 1);
7094 Set_Parent
(Hi_Bound
, P
);
7095 Analyze_And_Resolve
(Hi_Bound
, Etype
(Lo_Bound
));
7098 -- For non-array case, just get bounds of scalar type
7100 elsif Is_Scalar_Type
(P_Type
) then
7103 -- For a fixed-point type, we must freeze to get the attributes
7104 -- of the fixed-point type set now so we can reference them.
7106 if Is_Fixed_Point_Type
(P_Type
)
7107 and then not Is_Frozen
(Base_Type
(P_Type
))
7108 and then Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
7109 and then Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
7111 Freeze_Fixed_Point_Type
(Base_Type
(P_Type
));
7114 -- For array case, get type of proper index
7120 Ndim
:= UI_To_Int
(Expr_Value
(E1
));
7123 Indx
:= First_Index
(P_Type
);
7124 for J
in 1 .. Ndim
- 1 loop
7128 -- If no index type, get out (some other error occurred, and
7129 -- we don't have enough information to complete the job).
7137 Ityp
:= Etype
(Indx
);
7140 -- A discrete range in an index constraint is allowed to be a
7141 -- subtype indication. This is syntactically a pain, but should
7142 -- not propagate to the entity for the corresponding index subtype.
7143 -- After checking that the subtype indication is legal, the range
7144 -- of the subtype indication should be transfered to the entity.
7145 -- The attributes for the bounds should remain the simple retrievals
7146 -- that they are now.
7148 Lo_Bound
:= Type_Low_Bound
(Ityp
);
7149 Hi_Bound
:= Type_High_Bound
(Ityp
);
7151 -- If subtype is non-static, result is definitely non-static
7153 if not Is_Static_Subtype
(Ityp
) then
7155 Set_Is_Static_Expression
(N
, False);
7157 -- Subtype is static, does it raise CE?
7159 elsif not Is_OK_Static_Subtype
(Ityp
) then
7160 Set_Raises_Constraint_Error
(N
);
7164 -------------------------------
7165 -- Statically_Denotes_Entity --
7166 -------------------------------
7168 function Statically_Denotes_Entity
(N
: Node_Id
) return Boolean is
7172 if not Is_Entity_Name
(N
) then
7179 Nkind
(Parent
(E
)) /= N_Object_Renaming_Declaration
7180 or else Statically_Denotes_Entity
(Renamed_Object
(E
));
7181 end Statically_Denotes_Entity
;
7183 -- Start of processing for Eval_Attribute
7186 -- Initialize result as non-static, will be reset if appropriate
7188 Set_Is_Static_Expression
(N
, False);
7191 -- Acquire first two expressions (at the moment, no attributes take more
7192 -- than two expressions in any case).
7194 if Present
(Expressions
(N
)) then
7195 E1
:= First
(Expressions
(N
));
7202 -- Special processing for Enabled attribute. This attribute has a very
7203 -- special prefix, and the easiest way to avoid lots of special checks
7204 -- to protect this special prefix from causing trouble is to deal with
7205 -- this attribute immediately and be done with it.
7207 if Id
= Attribute_Enabled
then
7209 -- We skip evaluation if the expander is not active. This is not just
7210 -- an optimization. It is of key importance that we not rewrite the
7211 -- attribute in a generic template, since we want to pick up the
7212 -- setting of the check in the instance, Testing Expander_Active
7213 -- might seem an easy way of doing this, but we need to account for
7214 -- ASIS needs, so check explicitly for a generic context.
7216 if not Inside_A_Generic
then
7218 C
: constant Check_Id
:= Get_Check_Id
(Chars
(P
));
7223 if C
in Predefined_Check_Id
then
7224 R
:= Scope_Suppress
.Suppress
(C
);
7226 R
:= Is_Check_Suppressed
(Empty
, C
);
7230 R
:= Is_Check_Suppressed
(Entity
(E1
), C
);
7233 Rewrite
(N
, New_Occurrence_Of
(Boolean_Literals
(not R
), Loc
));
7240 -- Attribute 'Img applied to a static enumeration value is static, and
7241 -- we will do the folding right here (things get confused if we let this
7242 -- case go through the normal circuitry).
7244 if Attribute_Name
(N
) = Name_Img
7245 and then Is_Entity_Name
(P
)
7246 and then Is_Enumeration_Type
(Etype
(Entity
(P
)))
7247 and then Is_OK_Static_Expression
(P
)
7250 Lit
: constant Entity_Id
:= Expr_Value_E
(P
);
7255 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
7256 Set_Casing
(All_Upper_Case
);
7257 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
7260 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
7261 Analyze_And_Resolve
(N
, Standard_String
);
7262 Set_Is_Static_Expression
(N
, True);
7268 -- Special processing for cases where the prefix is an object. For this
7269 -- purpose, a string literal counts as an object (attributes of string
7270 -- literals can only appear in generated code).
7272 if Is_Object_Reference
(P
) or else Nkind
(P
) = N_String_Literal
then
7274 -- For Component_Size, the prefix is an array object, and we apply
7275 -- the attribute to the type of the object. This is allowed for both
7276 -- unconstrained and constrained arrays, since the bounds have no
7277 -- influence on the value of this attribute.
7279 if Id
= Attribute_Component_Size
then
7280 P_Entity
:= Etype
(P
);
7282 -- For Enum_Rep, evaluation depends on the nature of the prefix and
7283 -- the optional argument.
7285 elsif Id
= Attribute_Enum_Rep
then
7286 if Is_Entity_Name
(P
) then
7288 -- The prefix denotes a constant or an enumeration literal, the
7289 -- attribute can be folded. A generated loop variable for an
7290 -- iterator is a constant, but cannot be constant-folded.
7292 if Ekind
(Entity
(P
)) = E_Enumeration_Literal
7294 (Ekind
(Entity
(P
)) = E_Constant
7295 and then Ekind
(Scope
(Entity
(P
))) /= E_Loop
)
7297 P_Entity
:= Etype
(P
);
7299 -- The prefix denotes an enumeration type. Folding can occur
7300 -- when the argument is a constant or an enumeration literal.
7302 elsif Is_Enumeration_Type
(Entity
(P
))
7303 and then Present
(E1
)
7304 and then Is_Entity_Name
(E1
)
7305 and then Ekind_In
(Entity
(E1
), E_Constant
,
7306 E_Enumeration_Literal
)
7308 P_Entity
:= Etype
(P
);
7310 -- Otherwise the attribute must be expanded into a conversion
7311 -- and evaluated at run time.
7318 -- Otherwise the attribute is illegal, do not attempt to perform
7319 -- any kind of folding.
7325 -- For First and Last, the prefix is an array object, and we apply
7326 -- the attribute to the type of the array, but we need a constrained
7327 -- type for this, so we use the actual subtype if available.
7329 elsif Id
= Attribute_First
or else
7330 Id
= Attribute_Last
or else
7331 Id
= Attribute_Length
7334 AS
: constant Entity_Id
:= Get_Actual_Subtype_If_Available
(P
);
7337 if Present
(AS
) and then Is_Constrained
(AS
) then
7340 -- If we have an unconstrained type we cannot fold
7348 -- For Size, give size of object if available, otherwise we
7349 -- cannot fold Size.
7351 elsif Id
= Attribute_Size
then
7352 if Is_Entity_Name
(P
)
7353 and then Known_Esize
(Entity
(P
))
7355 Compile_Time_Known_Attribute
(N
, Esize
(Entity
(P
)));
7363 -- For Alignment, give size of object if available, otherwise we
7364 -- cannot fold Alignment.
7366 elsif Id
= Attribute_Alignment
then
7367 if Is_Entity_Name
(P
)
7368 and then Known_Alignment
(Entity
(P
))
7370 Fold_Uint
(N
, Alignment
(Entity
(P
)), Static
);
7378 -- For Lock_Free, we apply the attribute to the type of the object.
7379 -- This is allowed since we have already verified that the type is a
7382 elsif Id
= Attribute_Lock_Free
then
7383 P_Entity
:= Etype
(P
);
7385 -- No other attributes for objects are folded
7392 -- Cases where P is not an object. Cannot do anything if P is not the
7393 -- name of an entity.
7395 elsif not Is_Entity_Name
(P
) then
7399 -- Otherwise get prefix entity
7402 P_Entity
:= Entity
(P
);
7405 -- If we are asked to evaluate an attribute where the prefix is a
7406 -- non-frozen generic actual type whose RM_Size is still set to zero,
7407 -- then abandon the effort.
7409 if Is_Type
(P_Entity
)
7410 and then (not Is_Frozen
(P_Entity
)
7411 and then Is_Generic_Actual_Type
(P_Entity
)
7412 and then RM_Size
(P_Entity
) = 0)
7414 -- However, the attribute Unconstrained_Array must be evaluated,
7415 -- since it is documented to be a static attribute (and can for
7416 -- example appear in a Compile_Time_Warning pragma). The frozen
7417 -- status of the type does not affect its evaluation.
7419 and then Id
/= Attribute_Unconstrained_Array
7424 -- At this stage P_Entity is the entity to which the attribute
7425 -- is to be applied. This is usually simply the entity of the
7426 -- prefix, except in some cases of attributes for objects, where
7427 -- as described above, we apply the attribute to the object type.
7429 -- Here is where we make sure that static attributes are properly
7430 -- marked as such. These are attributes whose prefix is a static
7431 -- scalar subtype, whose result is scalar, and whose arguments, if
7432 -- present, are static scalar expressions. Note that such references
7433 -- are static expressions even if they raise Constraint_Error.
7435 -- For example, Boolean'Pos (1/0 = 0) is a static expression, even
7436 -- though evaluating it raises constraint error. This means that a
7437 -- declaration like:
7439 -- X : constant := (if True then 1 else Boolean'Pos (1/0 = 0));
7441 -- is legal, since here this expression appears in a statically
7442 -- unevaluated position, so it does not actually raise an exception.
7444 if Is_Scalar_Type
(P_Entity
)
7445 and then (not Is_Generic_Type
(P_Entity
))
7446 and then Is_Static_Subtype
(P_Entity
)
7447 and then Is_Scalar_Type
(Etype
(N
))
7450 or else (Is_Static_Expression
(E1
)
7451 and then Is_Scalar_Type
(Etype
(E1
))))
7454 or else (Is_Static_Expression
(E2
)
7455 and then Is_Scalar_Type
(Etype
(E1
))))
7458 Set_Is_Static_Expression
(N
, True);
7461 -- First foldable possibility is a scalar or array type (RM 4.9(7))
7462 -- that is not generic (generic types are eliminated by RM 4.9(25)).
7463 -- Note we allow non-static non-generic types at this stage as further
7466 if Is_Type
(P_Entity
)
7467 and then (Is_Scalar_Type
(P_Entity
) or Is_Array_Type
(P_Entity
))
7468 and then (not Is_Generic_Type
(P_Entity
))
7472 -- Second foldable possibility is an array object (RM 4.9(8))
7474 elsif Ekind_In
(P_Entity
, E_Variable
, E_Constant
)
7475 and then Is_Array_Type
(Etype
(P_Entity
))
7476 and then (not Is_Generic_Type
(Etype
(P_Entity
)))
7478 P_Type
:= Etype
(P_Entity
);
7480 -- If the entity is an array constant with an unconstrained nominal
7481 -- subtype then get the type from the initial value. If the value has
7482 -- been expanded into assignments, there is no expression and the
7483 -- attribute reference remains dynamic.
7485 -- We could do better here and retrieve the type ???
7487 if Ekind
(P_Entity
) = E_Constant
7488 and then not Is_Constrained
(P_Type
)
7490 if No
(Constant_Value
(P_Entity
)) then
7493 P_Type
:= Etype
(Constant_Value
(P_Entity
));
7497 -- Definite must be folded if the prefix is not a generic type, that
7498 -- is to say if we are within an instantiation. Same processing applies
7499 -- to the GNAT attributes Atomic_Always_Lock_Free, Has_Discriminants,
7500 -- Lock_Free, Type_Class, Has_Tagged_Value, and Unconstrained_Array.
7502 elsif (Id
= Attribute_Atomic_Always_Lock_Free
or else
7503 Id
= Attribute_Definite
or else
7504 Id
= Attribute_Has_Access_Values
or else
7505 Id
= Attribute_Has_Discriminants
or else
7506 Id
= Attribute_Has_Tagged_Values
or else
7507 Id
= Attribute_Lock_Free
or else
7508 Id
= Attribute_Type_Class
or else
7509 Id
= Attribute_Unconstrained_Array
or else
7510 Id
= Attribute_Max_Alignment_For_Allocation
)
7511 and then not Is_Generic_Type
(P_Entity
)
7515 -- We can fold 'Size applied to a type if the size is known (as happens
7516 -- for a size from an attribute definition clause). At this stage, this
7517 -- can happen only for types (e.g. record types) for which the size is
7518 -- always non-static. We exclude generic types from consideration (since
7519 -- they have bogus sizes set within templates).
7521 elsif Id
= Attribute_Size
7522 and then Is_Type
(P_Entity
)
7523 and then (not Is_Generic_Type
(P_Entity
))
7524 and then Known_Static_RM_Size
(P_Entity
)
7526 Compile_Time_Known_Attribute
(N
, RM_Size
(P_Entity
));
7529 -- We can fold 'Alignment applied to a type if the alignment is known
7530 -- (as happens for an alignment from an attribute definition clause).
7531 -- At this stage, this can happen only for types (e.g. record types) for
7532 -- which the size is always non-static. We exclude generic types from
7533 -- consideration (since they have bogus sizes set within templates).
7535 elsif Id
= Attribute_Alignment
7536 and then Is_Type
(P_Entity
)
7537 and then (not Is_Generic_Type
(P_Entity
))
7538 and then Known_Alignment
(P_Entity
)
7540 Compile_Time_Known_Attribute
(N
, Alignment
(P_Entity
));
7543 -- If this is an access attribute that is known to fail accessibility
7544 -- check, rewrite accordingly.
7546 elsif Attribute_Name
(N
) = Name_Access
7547 and then Raises_Constraint_Error
(N
)
7550 Make_Raise_Program_Error
(Loc
,
7551 Reason
=> PE_Accessibility_Check_Failed
));
7552 Set_Etype
(N
, C_Type
);
7555 -- No other cases are foldable (they certainly aren't static, and at
7556 -- the moment we don't try to fold any cases other than the ones above).
7563 -- If either attribute or the prefix is Any_Type, then propagate
7564 -- Any_Type to the result and don't do anything else at all.
7566 if P_Type
= Any_Type
7567 or else (Present
(E1
) and then Etype
(E1
) = Any_Type
)
7568 or else (Present
(E2
) and then Etype
(E2
) = Any_Type
)
7570 Set_Etype
(N
, Any_Type
);
7574 -- Scalar subtype case. We have not yet enforced the static requirement
7575 -- of (RM 4.9(7)) and we don't intend to just yet, since there are cases
7576 -- of non-static attribute references (e.g. S'Digits for a non-static
7577 -- floating-point type, which we can compute at compile time).
7579 -- Note: this folding of non-static attributes is not simply a case of
7580 -- optimization. For many of the attributes affected, Gigi cannot handle
7581 -- the attribute and depends on the front end having folded them away.
7583 -- Note: although we don't require staticness at this stage, we do set
7584 -- the Static variable to record the staticness, for easy reference by
7585 -- those attributes where it matters (e.g. Succ and Pred), and also to
7586 -- be used to ensure that non-static folded things are not marked as
7587 -- being static (a check that is done right at the end).
7589 P_Root_Type
:= Root_Type
(P_Type
);
7590 P_Base_Type
:= Base_Type
(P_Type
);
7592 -- If the root type or base type is generic, then we cannot fold. This
7593 -- test is needed because subtypes of generic types are not always
7594 -- marked as being generic themselves (which seems odd???)
7596 if Is_Generic_Type
(P_Root_Type
)
7597 or else Is_Generic_Type
(P_Base_Type
)
7602 if Is_Scalar_Type
(P_Type
) then
7603 if not Is_Static_Subtype
(P_Type
) then
7605 Set_Is_Static_Expression
(N
, False);
7606 elsif not Is_OK_Static_Subtype
(P_Type
) then
7607 Set_Raises_Constraint_Error
(N
);
7610 -- Array case. We enforce the constrained requirement of (RM 4.9(7-8))
7611 -- since we can't do anything with unconstrained arrays. In addition,
7612 -- only the First, Last and Length attributes are possibly static.
7614 -- Atomic_Always_Lock_Free, Definite, Has_Access_Values,
7615 -- Has_Discriminants, Has_Tagged_Values, Lock_Free, Type_Class, and
7616 -- Unconstrained_Array are again exceptions, because they apply as well
7617 -- to unconstrained types.
7619 -- In addition Component_Size is an exception since it is possibly
7620 -- foldable, even though it is never static, and it does apply to
7621 -- unconstrained arrays. Furthermore, it is essential to fold this
7622 -- in the packed case, since otherwise the value will be incorrect.
7624 elsif Id
= Attribute_Atomic_Always_Lock_Free
or else
7625 Id
= Attribute_Definite
or else
7626 Id
= Attribute_Has_Access_Values
or else
7627 Id
= Attribute_Has_Discriminants
or else
7628 Id
= Attribute_Has_Tagged_Values
or else
7629 Id
= Attribute_Lock_Free
or else
7630 Id
= Attribute_Type_Class
or else
7631 Id
= Attribute_Unconstrained_Array
or else
7632 Id
= Attribute_Component_Size
7635 Set_Is_Static_Expression
(N
, False);
7637 elsif Id
/= Attribute_Max_Alignment_For_Allocation
then
7638 if not Is_Constrained
(P_Type
)
7639 or else (Id
/= Attribute_First
and then
7640 Id
/= Attribute_Last
and then
7641 Id
/= Attribute_Length
)
7647 -- The rules in (RM 4.9(7,8)) require a static array, but as in the
7648 -- scalar case, we hold off on enforcing staticness, since there are
7649 -- cases which we can fold at compile time even though they are not
7650 -- static (e.g. 'Length applied to a static index, even though other
7651 -- non-static indexes make the array type non-static). This is only
7652 -- an optimization, but it falls out essentially free, so why not.
7653 -- Again we compute the variable Static for easy reference later
7654 -- (note that no array attributes are static in Ada 83).
7656 -- We also need to set Static properly for subsequent legality checks
7657 -- which might otherwise accept non-static constants in contexts
7658 -- where they are not legal.
7661 Ada_Version
>= Ada_95
and then Statically_Denotes_Entity
(P
);
7662 Set_Is_Static_Expression
(N
, Static
);
7668 Nod
:= First_Index
(P_Type
);
7670 -- The expression is static if the array type is constrained
7671 -- by given bounds, and not by an initial expression. Constant
7672 -- strings are static in any case.
7674 if Root_Type
(P_Type
) /= Standard_String
then
7676 Static
and then not Is_Constr_Subt_For_U_Nominal
(P_Type
);
7677 Set_Is_Static_Expression
(N
, Static
);
7680 while Present
(Nod
) loop
7681 if not Is_Static_Subtype
(Etype
(Nod
)) then
7683 Set_Is_Static_Expression
(N
, False);
7685 elsif not Is_OK_Static_Subtype
(Etype
(Nod
)) then
7686 Set_Raises_Constraint_Error
(N
);
7688 Set_Is_Static_Expression
(N
, False);
7691 -- If however the index type is generic, or derived from
7692 -- one, attributes cannot be folded.
7694 if Is_Generic_Type
(Root_Type
(Etype
(Nod
)))
7695 and then Id
/= Attribute_Component_Size
7705 -- Check any expressions that are present. Note that these expressions,
7706 -- depending on the particular attribute type, are either part of the
7707 -- attribute designator, or they are arguments in a case where the
7708 -- attribute reference returns a function. In the latter case, the
7709 -- rule in (RM 4.9(22)) applies and in particular requires the type
7710 -- of the expressions to be scalar in order for the attribute to be
7711 -- considered to be static.
7719 while Present
(E
) loop
7721 -- If expression is not static, then the attribute reference
7722 -- result certainly cannot be static.
7724 if not Is_Static_Expression
(E
) then
7726 Set_Is_Static_Expression
(N
, False);
7729 if Raises_Constraint_Error
(E
) then
7730 Set_Raises_Constraint_Error
(N
);
7733 -- If the result is not known at compile time, or is not of
7734 -- a scalar type, then the result is definitely not static,
7735 -- so we can quit now.
7737 if not Compile_Time_Known_Value
(E
)
7738 or else not Is_Scalar_Type
(Etype
(E
))
7740 -- An odd special case, if this is a Pos attribute, this
7741 -- is where we need to apply a range check since it does
7742 -- not get done anywhere else.
7744 if Id
= Attribute_Pos
then
7745 if Is_Integer_Type
(Etype
(E
)) then
7746 Apply_Range_Check
(E
, Etype
(N
));
7753 -- If the expression raises a constraint error, then so does
7754 -- the attribute reference. We keep going in this case because
7755 -- we are still interested in whether the attribute reference
7756 -- is static even if it is not static.
7758 elsif Raises_Constraint_Error
(E
) then
7759 Set_Raises_Constraint_Error
(N
);
7765 if Raises_Constraint_Error
(Prefix
(N
)) then
7766 Set_Is_Static_Expression
(N
, False);
7771 -- Deal with the case of a static attribute reference that raises
7772 -- constraint error. The Raises_Constraint_Error flag will already
7773 -- have been set, and the Static flag shows whether the attribute
7774 -- reference is static. In any case we certainly can't fold such an
7775 -- attribute reference.
7777 -- Note that the rewriting of the attribute node with the constraint
7778 -- error node is essential in this case, because otherwise Gigi might
7779 -- blow up on one of the attributes it never expects to see.
7781 -- The constraint_error node must have the type imposed by the context,
7782 -- to avoid spurious errors in the enclosing expression.
7784 if Raises_Constraint_Error
(N
) then
7786 Make_Raise_Constraint_Error
(Sloc
(N
),
7787 Reason
=> CE_Range_Check_Failed
);
7788 Set_Etype
(CE_Node
, Etype
(N
));
7789 Set_Raises_Constraint_Error
(CE_Node
);
7791 Rewrite
(N
, Relocate_Node
(CE_Node
));
7792 Set_Raises_Constraint_Error
(N
, True);
7796 -- At this point we have a potentially foldable attribute reference.
7797 -- If Static is set, then the attribute reference definitely obeys
7798 -- the requirements in (RM 4.9(7,8,22)), and it definitely can be
7799 -- folded. If Static is not set, then the attribute may or may not
7800 -- be foldable, and the individual attribute processing routines
7801 -- test Static as required in cases where it makes a difference.
7803 -- In the case where Static is not set, we do know that all the
7804 -- expressions present are at least known at compile time (we assumed
7805 -- above that if this was not the case, then there was no hope of static
7806 -- evaluation). However, we did not require that the bounds of the
7807 -- prefix type be compile time known, let alone static). That's because
7808 -- there are many attributes that can be computed at compile time on
7809 -- non-static subtypes, even though such references are not static
7812 -- For VAX float, the root type is an IEEE type. So make sure to use the
7813 -- base type instead of the root-type for floating point attributes.
7817 -- Attributes related to Ada 2012 iterators (placeholder ???)
7819 when Attribute_Constant_Indexing |
7820 Attribute_Default_Iterator |
7821 Attribute_Implicit_Dereference |
7822 Attribute_Iterator_Element |
7823 Attribute_Iterable |
7824 Attribute_Variable_Indexing
=> null;
7826 -- Internal attributes used to deal with Ada 2012 delayed aspects.
7827 -- These were already rejected by the parser. Thus they shouldn't
7830 when Internal_Attribute_Id
=>
7831 raise Program_Error
;
7837 when Attribute_Adjacent
=>
7841 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
7848 when Attribute_Aft
=>
7849 Fold_Uint
(N
, Aft_Value
(P_Type
), Static
);
7855 when Attribute_Alignment
=> Alignment_Block
: declare
7856 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
7859 -- Fold if alignment is set and not otherwise
7861 if Known_Alignment
(P_TypeA
) then
7862 Fold_Uint
(N
, Alignment
(P_TypeA
), Static
);
7864 end Alignment_Block
;
7866 -----------------------------
7867 -- Atomic_Always_Lock_Free --
7868 -----------------------------
7870 -- Atomic_Always_Lock_Free attribute is a Boolean, thus no need to fold
7873 when Attribute_Atomic_Always_Lock_Free
=> Atomic_Always_Lock_Free
:
7875 V
: constant Entity_Id
:=
7877 (Support_Atomic_Primitives_On_Target
7878 and then Support_Atomic_Primitives
(P_Type
));
7881 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
7883 -- Analyze and resolve as boolean. Note that this attribute is a
7884 -- static attribute in GNAT.
7886 Analyze_And_Resolve
(N
, Standard_Boolean
);
7888 Set_Is_Static_Expression
(N
, True);
7889 end Atomic_Always_Lock_Free
;
7895 -- Bit can never be folded
7897 when Attribute_Bit
=>
7904 -- Body_version can never be static
7906 when Attribute_Body_Version
=>
7913 when Attribute_Ceiling
=>
7915 (N
, Eval_Fat
.Ceiling
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
7917 --------------------
7918 -- Component_Size --
7919 --------------------
7921 when Attribute_Component_Size
=>
7922 if Known_Static_Component_Size
(P_Type
) then
7923 Fold_Uint
(N
, Component_Size
(P_Type
), Static
);
7930 when Attribute_Compose
=>
7933 Eval_Fat
.Compose
(P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
7940 -- Constrained is never folded for now, there may be cases that
7941 -- could be handled at compile time. To be looked at later.
7943 when Attribute_Constrained
=>
7945 -- The expander might fold it and set the static flag accordingly,
7946 -- but with expansion disabled (as in ASIS), it remains as an
7947 -- attribute reference, and this reference is not static.
7949 Set_Is_Static_Expression
(N
, False);
7956 when Attribute_Copy_Sign
=>
7960 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value_R
(E2
)),
7967 when Attribute_Definite
=>
7968 Rewrite
(N
, New_Occurrence_Of
(
7969 Boolean_Literals
(Is_Definite_Subtype
(P_Entity
)), Loc
));
7970 Analyze_And_Resolve
(N
, Standard_Boolean
);
7976 when Attribute_Delta
=>
7977 Fold_Ureal
(N
, Delta_Value
(P_Type
), True);
7983 when Attribute_Denorm
=>
7985 (N
, UI_From_Int
(Boolean'Pos (Has_Denormals
(P_Type
))), Static
);
7987 ---------------------
7988 -- Descriptor_Size --
7989 ---------------------
7991 when Attribute_Descriptor_Size
=>
7998 when Attribute_Digits
=>
7999 Fold_Uint
(N
, Digits_Value
(P_Type
), Static
);
8005 when Attribute_Emax
=>
8007 -- Ada 83 attribute is defined as (RM83 3.5.8)
8009 -- T'Emax = 4 * T'Mantissa
8011 Fold_Uint
(N
, 4 * Mantissa
, Static
);
8017 when Attribute_Enum_Rep
=> Enum_Rep
: declare
8021 -- The attribute appears in the form:
8023 -- Enum_Typ'Enum_Rep (Const)
8024 -- Enum_Typ'Enum_Rep (Enum_Lit)
8026 if Present
(E1
) then
8029 -- Otherwise the prefix denotes a constant or enumeration literal:
8032 -- Enum_Lit'Enum_Rep
8038 -- For an enumeration type with a non-standard representation use
8039 -- the Enumeration_Rep field of the proper constant. Note that this
8040 -- will not work for types Character/Wide_[Wide-]Character, since no
8041 -- real entities are created for the enumeration literals, but that
8042 -- does not matter since these two types do not have non-standard
8043 -- representations anyway.
8045 if Is_Enumeration_Type
(P_Type
)
8046 and then Has_Non_Standard_Rep
(P_Type
)
8048 Fold_Uint
(N
, Enumeration_Rep
(Expr_Value_E
(Val
)), Static
);
8050 -- For enumeration types with standard representations and all other
8051 -- cases (i.e. all integer and modular types), Enum_Rep is equivalent
8055 Fold_Uint
(N
, Expr_Value
(Val
), Static
);
8063 when Attribute_Enum_Val
=> Enum_Val
: declare
8067 -- We have something like Enum_Type'Enum_Val (23), so search for a
8068 -- corresponding value in the list of Enum_Rep values for the type.
8070 Lit
:= First_Literal
(P_Base_Type
);
8072 if Enumeration_Rep
(Lit
) = Expr_Value
(E1
) then
8073 Fold_Uint
(N
, Enumeration_Pos
(Lit
), Static
);
8080 Apply_Compile_Time_Constraint_Error
8081 (N
, "no representation value matches",
8082 CE_Range_Check_Failed
,
8083 Warn
=> not Static
);
8093 when Attribute_Epsilon
=>
8095 -- Ada 83 attribute is defined as (RM83 3.5.8)
8097 -- T'Epsilon = 2.0**(1 - T'Mantissa)
8099 Fold_Ureal
(N
, Ureal_2
** (1 - Mantissa
), True);
8105 when Attribute_Exponent
=>
8107 Eval_Fat
.Exponent
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8113 when Attribute_First
=> First_Attr
:
8117 if Compile_Time_Known_Value
(Lo_Bound
) then
8118 if Is_Real_Type
(P_Type
) then
8119 Fold_Ureal
(N
, Expr_Value_R
(Lo_Bound
), Static
);
8121 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8125 Check_Concurrent_Discriminant
(Lo_Bound
);
8133 when Attribute_First_Valid
=> First_Valid
:
8135 if Has_Predicates
(P_Type
)
8136 and then Has_Static_Predicate
(P_Type
)
8139 FirstN
: constant Node_Id
:=
8140 First
(Static_Discrete_Predicate
(P_Type
));
8142 if Nkind
(FirstN
) = N_Range
then
8143 Fold_Uint
(N
, Expr_Value
(Low_Bound
(FirstN
)), Static
);
8145 Fold_Uint
(N
, Expr_Value
(FirstN
), Static
);
8151 Fold_Uint
(N
, Expr_Value
(Lo_Bound
), Static
);
8159 when Attribute_Fixed_Value
=>
8166 when Attribute_Floor
=>
8168 (N
, Eval_Fat
.Floor
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8174 when Attribute_Fore
=>
8175 if Compile_Time_Known_Bounds
(P_Type
) then
8176 Fold_Uint
(N
, UI_From_Int
(Fore_Value
), Static
);
8183 when Attribute_Fraction
=>
8185 (N
, Eval_Fat
.Fraction
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8187 -----------------------
8188 -- Has_Access_Values --
8189 -----------------------
8191 when Attribute_Has_Access_Values
=>
8192 Rewrite
(N
, New_Occurrence_Of
8193 (Boolean_Literals
(Has_Access_Values
(P_Root_Type
)), Loc
));
8194 Analyze_And_Resolve
(N
, Standard_Boolean
);
8196 -----------------------
8197 -- Has_Discriminants --
8198 -----------------------
8200 when Attribute_Has_Discriminants
=>
8201 Rewrite
(N
, New_Occurrence_Of
(
8202 Boolean_Literals
(Has_Discriminants
(P_Entity
)), Loc
));
8203 Analyze_And_Resolve
(N
, Standard_Boolean
);
8205 ----------------------
8206 -- Has_Same_Storage --
8207 ----------------------
8209 when Attribute_Has_Same_Storage
=>
8212 -----------------------
8213 -- Has_Tagged_Values --
8214 -----------------------
8216 when Attribute_Has_Tagged_Values
=>
8217 Rewrite
(N
, New_Occurrence_Of
8218 (Boolean_Literals
(Has_Tagged_Component
(P_Root_Type
)), Loc
));
8219 Analyze_And_Resolve
(N
, Standard_Boolean
);
8225 when Attribute_Identity
=>
8232 -- Image is a scalar attribute, but is never static, because it is
8233 -- not a static function (having a non-scalar argument (RM 4.9(22))
8234 -- However, we can constant-fold the image of an enumeration literal
8235 -- if names are available.
8237 when Attribute_Image
=>
8238 if Is_Entity_Name
(E1
)
8239 and then Ekind
(Entity
(E1
)) = E_Enumeration_Literal
8240 and then not Discard_Names
(First_Subtype
(Etype
(E1
)))
8241 and then not Global_Discard_Names
8244 Lit
: constant Entity_Id
:= Entity
(E1
);
8248 Get_Unqualified_Decoded_Name_String
(Chars
(Lit
));
8249 Set_Casing
(All_Upper_Case
);
8250 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
8252 Rewrite
(N
, Make_String_Literal
(Loc
, Strval
=> Str
));
8253 Analyze_And_Resolve
(N
, Standard_String
);
8254 Set_Is_Static_Expression
(N
, False);
8262 -- We never try to fold Integer_Value (though perhaps we could???)
8264 when Attribute_Integer_Value
=>
8271 -- Invalid_Value is a scalar attribute that is never static, because
8272 -- the value is by design out of range.
8274 when Attribute_Invalid_Value
=>
8281 when Attribute_Large
=>
8283 -- For fixed-point, we use the identity:
8285 -- T'Large = (2.0**T'Mantissa - 1.0) * T'Small
8287 if Is_Fixed_Point_Type
(P_Type
) then
8289 Make_Op_Multiply
(Loc
,
8291 Make_Op_Subtract
(Loc
,
8295 Make_Real_Literal
(Loc
, Ureal_2
),
8297 Make_Attribute_Reference
(Loc
,
8299 Attribute_Name
=> Name_Mantissa
)),
8300 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_1
)),
8303 Make_Real_Literal
(Loc
, Small_Value
(Entity
(P
)))));
8305 Analyze_And_Resolve
(N
, C_Type
);
8307 -- Floating-point (Ada 83 compatibility)
8310 -- Ada 83 attribute is defined as (RM83 3.5.8)
8312 -- T'Large = 2.0**T'Emax * (1.0 - 2.0**(-T'Mantissa))
8316 -- T'Emax = 4 * T'Mantissa
8320 Ureal_2
** (4 * Mantissa
) * (Ureal_1
- Ureal_2
** (-Mantissa
)),
8328 when Attribute_Lock_Free
=> Lock_Free
: declare
8329 V
: constant Entity_Id
:= Boolean_Literals
(Uses_Lock_Free
(P_Type
));
8332 Rewrite
(N
, New_Occurrence_Of
(V
, Loc
));
8334 -- Analyze and resolve as boolean. Note that this attribute is a
8335 -- static attribute in GNAT.
8337 Analyze_And_Resolve
(N
, Standard_Boolean
);
8339 Set_Is_Static_Expression
(N
, True);
8346 when Attribute_Last
=> Last_Attr
:
8350 if Compile_Time_Known_Value
(Hi_Bound
) then
8351 if Is_Real_Type
(P_Type
) then
8352 Fold_Ureal
(N
, Expr_Value_R
(Hi_Bound
), Static
);
8354 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8358 Check_Concurrent_Discriminant
(Hi_Bound
);
8366 when Attribute_Last_Valid
=> Last_Valid
:
8368 if Has_Predicates
(P_Type
)
8369 and then Has_Static_Predicate
(P_Type
)
8372 LastN
: constant Node_Id
:=
8373 Last
(Static_Discrete_Predicate
(P_Type
));
8375 if Nkind
(LastN
) = N_Range
then
8376 Fold_Uint
(N
, Expr_Value
(High_Bound
(LastN
)), Static
);
8378 Fold_Uint
(N
, Expr_Value
(LastN
), Static
);
8384 Fold_Uint
(N
, Expr_Value
(Hi_Bound
), Static
);
8392 when Attribute_Leading_Part
=>
8395 Eval_Fat
.Leading_Part
8396 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
8403 when Attribute_Length
=> Length
: declare
8407 -- If any index type is a formal type, or derived from one, the
8408 -- bounds are not static. Treating them as static can produce
8409 -- spurious warnings or improper constant folding.
8411 Ind
:= First_Index
(P_Type
);
8412 while Present
(Ind
) loop
8413 if Is_Generic_Type
(Root_Type
(Etype
(Ind
))) then
8422 -- For two compile time values, we can compute length
8424 if Compile_Time_Known_Value
(Lo_Bound
)
8425 and then Compile_Time_Known_Value
(Hi_Bound
)
8428 UI_Max
(0, 1 + (Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
))),
8432 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8433 -- comparable, and we can figure out the difference between them.
8436 Diff
: aliased Uint
;
8440 Compile_Time_Compare
8441 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8444 Fold_Uint
(N
, Uint_1
, Static
);
8447 Fold_Uint
(N
, Uint_0
, Static
);
8450 if Diff
/= No_Uint
then
8451 Fold_Uint
(N
, Diff
+ 1, Static
);
8464 -- Loop_Entry acts as an alias of a constant initialized to the prefix
8465 -- of the said attribute at the point of entry into the related loop. As
8466 -- such, the attribute reference does not need to be evaluated because
8467 -- the prefix is the one that is evaluted.
8469 when Attribute_Loop_Entry
=>
8476 when Attribute_Machine
=>
8480 (P_Base_Type
, Expr_Value_R
(E1
), Eval_Fat
.Round
, N
),
8487 when Attribute_Machine_Emax
=>
8488 Fold_Uint
(N
, Machine_Emax_Value
(P_Type
), Static
);
8494 when Attribute_Machine_Emin
=>
8495 Fold_Uint
(N
, Machine_Emin_Value
(P_Type
), Static
);
8497 ----------------------
8498 -- Machine_Mantissa --
8499 ----------------------
8501 when Attribute_Machine_Mantissa
=>
8502 Fold_Uint
(N
, Machine_Mantissa_Value
(P_Type
), Static
);
8504 -----------------------
8505 -- Machine_Overflows --
8506 -----------------------
8508 when Attribute_Machine_Overflows
=>
8510 -- Always true for fixed-point
8512 if Is_Fixed_Point_Type
(P_Type
) then
8513 Fold_Uint
(N
, True_Value
, Static
);
8515 -- Floating point case
8519 UI_From_Int
(Boolean'Pos (Machine_Overflows_On_Target
)),
8527 when Attribute_Machine_Radix
=>
8528 if Is_Fixed_Point_Type
(P_Type
) then
8529 if Is_Decimal_Fixed_Point_Type
(P_Type
)
8530 and then Machine_Radix_10
(P_Type
)
8532 Fold_Uint
(N
, Uint_10
, Static
);
8534 Fold_Uint
(N
, Uint_2
, Static
);
8537 -- All floating-point type always have radix 2
8540 Fold_Uint
(N
, Uint_2
, Static
);
8543 ----------------------
8544 -- Machine_Rounding --
8545 ----------------------
8547 -- Note: for the folding case, it is fine to treat Machine_Rounding
8548 -- exactly the same way as Rounding, since this is one of the allowed
8549 -- behaviors, and performance is not an issue here. It might be a bit
8550 -- better to give the same result as it would give at run time, even
8551 -- though the non-determinism is certainly permitted.
8553 when Attribute_Machine_Rounding
=>
8555 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8557 --------------------
8558 -- Machine_Rounds --
8559 --------------------
8561 when Attribute_Machine_Rounds
=>
8563 -- Always False for fixed-point
8565 if Is_Fixed_Point_Type
(P_Type
) then
8566 Fold_Uint
(N
, False_Value
, Static
);
8568 -- Else yield proper floating-point result
8572 (N
, UI_From_Int
(Boolean'Pos (Machine_Rounds_On_Target
)),
8580 -- Note: Machine_Size is identical to Object_Size
8582 when Attribute_Machine_Size
=> Machine_Size
: declare
8583 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8586 if Known_Esize
(P_TypeA
) then
8587 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
8595 when Attribute_Mantissa
=>
8597 -- Fixed-point mantissa
8599 if Is_Fixed_Point_Type
(P_Type
) then
8601 -- Compile time foldable case
8603 if Compile_Time_Known_Value
(Type_Low_Bound
(P_Type
))
8605 Compile_Time_Known_Value
(Type_High_Bound
(P_Type
))
8607 -- The calculation of the obsolete Ada 83 attribute Mantissa
8608 -- is annoying, because of AI00143, quoted here:
8610 -- !question 84-01-10
8612 -- Consider the model numbers for F:
8614 -- type F is delta 1.0 range -7.0 .. 8.0;
8616 -- The wording requires that F'MANTISSA be the SMALLEST
8617 -- integer number for which each bound of the specified
8618 -- range is either a model number or lies at most small
8619 -- distant from a model number. This means F'MANTISSA
8620 -- is required to be 3 since the range -7.0 .. 7.0 fits
8621 -- in 3 signed bits, and 8 is "at most" 1.0 from a model
8622 -- number, namely, 7. Is this analysis correct? Note that
8623 -- this implies the upper bound of the range is not
8624 -- represented as a model number.
8626 -- !response 84-03-17
8628 -- The analysis is correct. The upper and lower bounds for
8629 -- a fixed point type can lie outside the range of model
8640 LBound
:= Expr_Value_R
(Type_Low_Bound
(P_Type
));
8641 UBound
:= Expr_Value_R
(Type_High_Bound
(P_Type
));
8642 Bound
:= UR_Max
(UR_Abs
(LBound
), UR_Abs
(UBound
));
8643 Max_Man
:= UR_Trunc
(Bound
/ Small_Value
(P_Type
));
8645 -- If the Bound is exactly a model number, i.e. a multiple
8646 -- of Small, then we back it off by one to get the integer
8647 -- value that must be representable.
8649 if Small_Value
(P_Type
) * Max_Man
= Bound
then
8650 Max_Man
:= Max_Man
- 1;
8653 -- Now find corresponding size = Mantissa value
8656 while 2 ** Siz
< Max_Man
loop
8660 Fold_Uint
(N
, Siz
, Static
);
8664 -- The case of dynamic bounds cannot be evaluated at compile
8665 -- time. Instead we use a runtime routine (see Exp_Attr).
8670 -- Floating-point Mantissa
8673 Fold_Uint
(N
, Mantissa
, Static
);
8680 when Attribute_Max
=> Max
:
8682 if Is_Real_Type
(P_Type
) then
8684 (N
, UR_Max
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
8686 Fold_Uint
(N
, UI_Max
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
8690 ----------------------------------
8691 -- Max_Alignment_For_Allocation --
8692 ----------------------------------
8694 -- Max_Alignment_For_Allocation is usually the Alignment. However,
8695 -- arrays are allocated with dope, so we need to take into account both
8696 -- the alignment of the array, which comes from the component alignment,
8697 -- and the alignment of the dope. Also, if the alignment is unknown, we
8698 -- use the max (it's OK to be pessimistic).
8700 when Attribute_Max_Alignment_For_Allocation
=>
8702 A
: Uint
:= UI_From_Int
(Ttypes
.Maximum_Alignment
);
8704 if Known_Alignment
(P_Type
) and then
8705 (not Is_Array_Type
(P_Type
) or else Alignment
(P_Type
) > A
)
8707 A
:= Alignment
(P_Type
);
8710 Fold_Uint
(N
, A
, Static
);
8713 ----------------------------------
8714 -- Max_Size_In_Storage_Elements --
8715 ----------------------------------
8717 -- Max_Size_In_Storage_Elements is simply the Size rounded up to a
8718 -- Storage_Unit boundary. We can fold any cases for which the size
8719 -- is known by the front end.
8721 when Attribute_Max_Size_In_Storage_Elements
=>
8722 if Known_Esize
(P_Type
) then
8724 (Esize
(P_Type
) + System_Storage_Unit
- 1) /
8725 System_Storage_Unit
,
8729 --------------------
8730 -- Mechanism_Code --
8731 --------------------
8733 when Attribute_Mechanism_Code
=>
8737 Mech
: Mechanism_Type
;
8741 Mech
:= Mechanism
(P_Entity
);
8744 Val
:= UI_To_Int
(Expr_Value
(E1
));
8746 Formal
:= First_Formal
(P_Entity
);
8747 for J
in 1 .. Val
- 1 loop
8748 Next_Formal
(Formal
);
8750 Mech
:= Mechanism
(Formal
);
8754 Fold_Uint
(N
, UI_From_Int
(Int
(-Mech
)), Static
);
8762 when Attribute_Min
=> Min
:
8764 if Is_Real_Type
(P_Type
) then
8766 (N
, UR_Min
(Expr_Value_R
(E1
), Expr_Value_R
(E2
)), Static
);
8769 (N
, UI_Min
(Expr_Value
(E1
), Expr_Value
(E2
)), Static
);
8777 when Attribute_Mod
=>
8779 (N
, UI_Mod
(Expr_Value
(E1
), Modulus
(P_Base_Type
)), Static
);
8785 when Attribute_Model
=>
8787 (N
, Eval_Fat
.Model
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8793 when Attribute_Model_Emin
=>
8794 Fold_Uint
(N
, Model_Emin_Value
(P_Base_Type
), Static
);
8800 when Attribute_Model_Epsilon
=>
8801 Fold_Ureal
(N
, Model_Epsilon_Value
(P_Base_Type
), Static
);
8803 --------------------
8804 -- Model_Mantissa --
8805 --------------------
8807 when Attribute_Model_Mantissa
=>
8808 Fold_Uint
(N
, Model_Mantissa_Value
(P_Base_Type
), Static
);
8814 when Attribute_Model_Small
=>
8815 Fold_Ureal
(N
, Model_Small_Value
(P_Base_Type
), Static
);
8821 when Attribute_Modulus
=>
8822 Fold_Uint
(N
, Modulus
(P_Type
), Static
);
8824 --------------------
8825 -- Null_Parameter --
8826 --------------------
8828 -- Cannot fold, we know the value sort of, but the whole point is
8829 -- that there is no way to talk about this imaginary value except
8830 -- by using the attribute, so we leave it the way it is.
8832 when Attribute_Null_Parameter
=>
8839 -- The Object_Size attribute for a type returns the Esize of the
8840 -- type and can be folded if this value is known.
8842 when Attribute_Object_Size
=> Object_Size
: declare
8843 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
8846 if Known_Esize
(P_TypeA
) then
8847 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
8851 ----------------------
8852 -- Overlaps_Storage --
8853 ----------------------
8855 when Attribute_Overlaps_Storage
=>
8858 -------------------------
8859 -- Passed_By_Reference --
8860 -------------------------
8862 -- Scalar types are never passed by reference
8864 when Attribute_Passed_By_Reference
=>
8865 Fold_Uint
(N
, False_Value
, Static
);
8871 when Attribute_Pos
=>
8872 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
8878 when Attribute_Pred
=> Pred
:
8880 -- Floating-point case
8882 if Is_Floating_Point_Type
(P_Type
) then
8884 (N
, Eval_Fat
.Pred
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
8888 elsif Is_Fixed_Point_Type
(P_Type
) then
8890 (N
, Expr_Value_R
(E1
) - Small_Value
(P_Type
), True);
8892 -- Modular integer case (wraps)
8894 elsif Is_Modular_Integer_Type
(P_Type
) then
8895 Fold_Uint
(N
, (Expr_Value
(E1
) - 1) mod Modulus
(P_Type
), Static
);
8897 -- Other scalar cases
8900 pragma Assert
(Is_Scalar_Type
(P_Type
));
8902 if Is_Enumeration_Type
(P_Type
)
8903 and then Expr_Value
(E1
) =
8904 Expr_Value
(Type_Low_Bound
(P_Base_Type
))
8906 Apply_Compile_Time_Constraint_Error
8907 (N
, "Pred of `&''First`",
8908 CE_Overflow_Check_Failed
,
8910 Warn
=> not Static
);
8916 Fold_Uint
(N
, Expr_Value
(E1
) - 1, Static
);
8924 -- No processing required, because by this stage, Range has been
8925 -- replaced by First .. Last, so this branch can never be taken.
8927 when Attribute_Range
=>
8928 raise Program_Error
;
8934 when Attribute_Range_Length
=>
8937 -- Can fold if both bounds are compile time known
8939 if Compile_Time_Known_Value
(Hi_Bound
)
8940 and then Compile_Time_Known_Value
(Lo_Bound
)
8944 (0, Expr_Value
(Hi_Bound
) - Expr_Value
(Lo_Bound
) + 1),
8948 -- One more case is where Hi_Bound and Lo_Bound are compile-time
8949 -- comparable, and we can figure out the difference between them.
8952 Diff
: aliased Uint
;
8956 Compile_Time_Compare
8957 (Lo_Bound
, Hi_Bound
, Diff
'Access, Assume_Valid
=> False)
8960 Fold_Uint
(N
, Uint_1
, Static
);
8963 Fold_Uint
(N
, Uint_0
, Static
);
8966 if Diff
/= No_Uint
then
8967 Fold_Uint
(N
, Diff
+ 1, Static
);
8979 when Attribute_Ref
=>
8980 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
8986 when Attribute_Remainder
=> Remainder
: declare
8987 X
: constant Ureal
:= Expr_Value_R
(E1
);
8988 Y
: constant Ureal
:= Expr_Value_R
(E2
);
8991 if UR_Is_Zero
(Y
) then
8992 Apply_Compile_Time_Constraint_Error
8993 (N
, "division by zero in Remainder",
8994 CE_Overflow_Check_Failed
,
8995 Warn
=> not Static
);
9001 Fold_Ureal
(N
, Eval_Fat
.Remainder
(P_Base_Type
, X
, Y
), Static
);
9008 when Attribute_Restriction_Set
=> Restriction_Set
: declare
9010 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
9011 Set_Is_Static_Expression
(N
);
9012 end Restriction_Set
;
9018 when Attribute_Round
=> Round
:
9024 -- First we get the (exact result) in units of small
9026 Sr
:= Expr_Value_R
(E1
) / Small_Value
(C_Type
);
9028 -- Now round that exactly to an integer
9030 Si
:= UR_To_Uint
(Sr
);
9032 -- Finally the result is obtained by converting back to real
9034 Fold_Ureal
(N
, Si
* Small_Value
(C_Type
), Static
);
9041 when Attribute_Rounding
=>
9043 (N
, Eval_Fat
.Rounding
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9049 when Attribute_Safe_Emax
=>
9050 Fold_Uint
(N
, Safe_Emax_Value
(P_Type
), Static
);
9056 when Attribute_Safe_First
=>
9057 Fold_Ureal
(N
, Safe_First_Value
(P_Type
), Static
);
9063 when Attribute_Safe_Large
=>
9064 if Is_Fixed_Point_Type
(P_Type
) then
9066 (N
, Expr_Value_R
(Type_High_Bound
(P_Base_Type
)), Static
);
9068 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9075 when Attribute_Safe_Last
=>
9076 Fold_Ureal
(N
, Safe_Last_Value
(P_Type
), Static
);
9082 when Attribute_Safe_Small
=>
9084 -- In Ada 95, the old Ada 83 attribute Safe_Small is redundant
9085 -- for fixed-point, since is the same as Small, but we implement
9086 -- it for backwards compatibility.
9088 if Is_Fixed_Point_Type
(P_Type
) then
9089 Fold_Ureal
(N
, Small_Value
(P_Type
), Static
);
9091 -- Ada 83 Safe_Small for floating-point cases
9094 Fold_Ureal
(N
, Model_Small_Value
(P_Type
), Static
);
9101 when Attribute_Scale
=>
9102 Fold_Uint
(N
, Scale_Value
(P_Type
), Static
);
9108 when Attribute_Scaling
=>
9112 (P_Base_Type
, Expr_Value_R
(E1
), Expr_Value
(E2
)),
9119 when Attribute_Signed_Zeros
=>
9121 (N
, UI_From_Int
(Boolean'Pos (Has_Signed_Zeros
(P_Type
))), Static
);
9127 -- Size attribute returns the RM size. All scalar types can be folded,
9128 -- as well as any types for which the size is known by the front end,
9129 -- including any type for which a size attribute is specified. This is
9130 -- one of the places where it is annoying that a size of zero means two
9131 -- things (zero size for scalars, unspecified size for non-scalars).
9133 when Attribute_Size | Attribute_VADS_Size
=> Size
: declare
9134 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9137 if Is_Scalar_Type
(P_TypeA
) or else RM_Size
(P_TypeA
) /= Uint_0
then
9141 if Id
= Attribute_VADS_Size
or else Use_VADS_Size
then
9143 S
: constant Node_Id
:= Size_Clause
(P_TypeA
);
9146 -- If a size clause applies, then use the size from it.
9147 -- This is one of the rare cases where we can use the
9148 -- Size_Clause field for a subtype when Has_Size_Clause
9149 -- is False. Consider:
9151 -- type x is range 1 .. 64;
9152 -- for x'size use 12;
9153 -- subtype y is x range 0 .. 3;
9155 -- Here y has a size clause inherited from x, but normally
9156 -- it does not apply, and y'size is 2. However, y'VADS_Size
9157 -- is indeed 12 and not 2.
9160 and then Is_OK_Static_Expression
(Expression
(S
))
9162 Fold_Uint
(N
, Expr_Value
(Expression
(S
)), Static
);
9164 -- If no size is specified, then we simply use the object
9165 -- size in the VADS_Size case (e.g. Natural'Size is equal
9166 -- to Integer'Size, not one less).
9169 Fold_Uint
(N
, Esize
(P_TypeA
), Static
);
9173 -- Normal case (Size) in which case we want the RM_Size
9176 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9185 when Attribute_Small
=>
9187 -- The floating-point case is present only for Ada 83 compatibility.
9188 -- Note that strictly this is an illegal addition, since we are
9189 -- extending an Ada 95 defined attribute, but we anticipate an
9190 -- ARG ruling that will permit this.
9192 if Is_Floating_Point_Type
(P_Type
) then
9194 -- Ada 83 attribute is defined as (RM83 3.5.8)
9196 -- T'Small = 2.0**(-T'Emax - 1)
9200 -- T'Emax = 4 * T'Mantissa
9202 Fold_Ureal
(N
, Ureal_2
** ((-(4 * Mantissa
)) - 1), Static
);
9204 -- Normal Ada 95 fixed-point case
9207 Fold_Ureal
(N
, Small_Value
(P_Type
), True);
9214 when Attribute_Stream_Size
=>
9221 when Attribute_Succ
=> Succ
:
9223 -- Floating-point case
9225 if Is_Floating_Point_Type
(P_Type
) then
9227 (N
, Eval_Fat
.Succ
(P_Base_Type
, Expr_Value_R
(E1
)), Static
);
9231 elsif Is_Fixed_Point_Type
(P_Type
) then
9232 Fold_Ureal
(N
, Expr_Value_R
(E1
) + Small_Value
(P_Type
), Static
);
9234 -- Modular integer case (wraps)
9236 elsif Is_Modular_Integer_Type
(P_Type
) then
9237 Fold_Uint
(N
, (Expr_Value
(E1
) + 1) mod Modulus
(P_Type
), Static
);
9239 -- Other scalar cases
9242 pragma Assert
(Is_Scalar_Type
(P_Type
));
9244 if Is_Enumeration_Type
(P_Type
)
9245 and then Expr_Value
(E1
) =
9246 Expr_Value
(Type_High_Bound
(P_Base_Type
))
9248 Apply_Compile_Time_Constraint_Error
9249 (N
, "Succ of `&''Last`",
9250 CE_Overflow_Check_Failed
,
9252 Warn
=> not Static
);
9257 Fold_Uint
(N
, Expr_Value
(E1
) + 1, Static
);
9266 when Attribute_Truncation
=>
9269 Eval_Fat
.Truncation
(P_Base_Type
, Expr_Value_R
(E1
)),
9276 when Attribute_Type_Class
=> Type_Class
: declare
9277 Typ
: constant Entity_Id
:= Underlying_Type
(P_Base_Type
);
9281 if Is_Descendant_Of_Address
(Typ
) then
9282 Id
:= RE_Type_Class_Address
;
9284 elsif Is_Enumeration_Type
(Typ
) then
9285 Id
:= RE_Type_Class_Enumeration
;
9287 elsif Is_Integer_Type
(Typ
) then
9288 Id
:= RE_Type_Class_Integer
;
9290 elsif Is_Fixed_Point_Type
(Typ
) then
9291 Id
:= RE_Type_Class_Fixed_Point
;
9293 elsif Is_Floating_Point_Type
(Typ
) then
9294 Id
:= RE_Type_Class_Floating_Point
;
9296 elsif Is_Array_Type
(Typ
) then
9297 Id
:= RE_Type_Class_Array
;
9299 elsif Is_Record_Type
(Typ
) then
9300 Id
:= RE_Type_Class_Record
;
9302 elsif Is_Access_Type
(Typ
) then
9303 Id
:= RE_Type_Class_Access
;
9305 elsif Is_Enumeration_Type
(Typ
) then
9306 Id
:= RE_Type_Class_Enumeration
;
9308 elsif Is_Task_Type
(Typ
) then
9309 Id
:= RE_Type_Class_Task
;
9311 -- We treat protected types like task types. It would make more
9312 -- sense to have another enumeration value, but after all the
9313 -- whole point of this feature is to be exactly DEC compatible,
9314 -- and changing the type Type_Class would not meet this requirement.
9316 elsif Is_Protected_Type
(Typ
) then
9317 Id
:= RE_Type_Class_Task
;
9319 -- Not clear if there are any other possibilities, but if there
9320 -- are, then we will treat them as the address case.
9323 Id
:= RE_Type_Class_Address
;
9326 Rewrite
(N
, New_Occurrence_Of
(RTE
(Id
), Loc
));
9329 -----------------------
9330 -- Unbiased_Rounding --
9331 -----------------------
9333 when Attribute_Unbiased_Rounding
=>
9336 Eval_Fat
.Unbiased_Rounding
(P_Base_Type
, Expr_Value_R
(E1
)),
9339 -------------------------
9340 -- Unconstrained_Array --
9341 -------------------------
9343 when Attribute_Unconstrained_Array
=> Unconstrained_Array
: declare
9344 Typ
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9347 Rewrite
(N
, New_Occurrence_Of
(
9349 Is_Array_Type
(P_Type
)
9350 and then not Is_Constrained
(Typ
)), Loc
));
9352 -- Analyze and resolve as boolean, note that this attribute is
9353 -- a static attribute in GNAT.
9355 Analyze_And_Resolve
(N
, Standard_Boolean
);
9357 Set_Is_Static_Expression
(N
, True);
9358 end Unconstrained_Array
;
9360 -- Attribute Update is never static
9362 when Attribute_Update
=>
9369 -- Processing is shared with Size
9375 when Attribute_Val
=> Val
:
9377 if Expr_Value
(E1
) < Expr_Value
(Type_Low_Bound
(P_Base_Type
))
9379 Expr_Value
(E1
) > Expr_Value
(Type_High_Bound
(P_Base_Type
))
9381 Apply_Compile_Time_Constraint_Error
9382 (N
, "Val expression out of range",
9383 CE_Range_Check_Failed
,
9384 Warn
=> not Static
);
9390 Fold_Uint
(N
, Expr_Value
(E1
), Static
);
9398 -- The Value_Size attribute for a type returns the RM size of the type.
9399 -- This an always be folded for scalar types, and can also be folded for
9400 -- non-scalar types if the size is set. This is one of the places where
9401 -- it is annoying that a size of zero means two things!
9403 when Attribute_Value_Size
=> Value_Size
: declare
9404 P_TypeA
: constant Entity_Id
:= Underlying_Type
(P_Type
);
9406 if Is_Scalar_Type
(P_TypeA
) or else RM_Size
(P_TypeA
) /= Uint_0
then
9407 Fold_Uint
(N
, RM_Size
(P_TypeA
), Static
);
9415 -- Version can never be static
9417 when Attribute_Version
=>
9424 -- Wide_Image is a scalar attribute, but is never static, because it
9425 -- is not a static function (having a non-scalar argument (RM 4.9(22))
9427 when Attribute_Wide_Image
=>
9430 ---------------------
9431 -- Wide_Wide_Image --
9432 ---------------------
9434 -- Wide_Wide_Image is a scalar attribute but is never static, because it
9435 -- is not a static function (having a non-scalar argument (RM 4.9(22)).
9437 when Attribute_Wide_Wide_Image
=>
9440 ---------------------
9441 -- Wide_Wide_Width --
9442 ---------------------
9444 -- Processing for Wide_Wide_Width is combined with Width
9450 -- Processing for Wide_Width is combined with Width
9456 -- This processing also handles the case of Wide_[Wide_]Width
9458 when Attribute_Width |
9459 Attribute_Wide_Width |
9460 Attribute_Wide_Wide_Width
=> Width
:
9462 if Compile_Time_Known_Bounds
(P_Type
) then
9464 -- Floating-point types
9466 if Is_Floating_Point_Type
(P_Type
) then
9468 -- Width is zero for a null range (RM 3.5 (38))
9470 if Expr_Value_R
(Type_High_Bound
(P_Type
)) <
9471 Expr_Value_R
(Type_Low_Bound
(P_Type
))
9473 Fold_Uint
(N
, Uint_0
, Static
);
9476 -- For floating-point, we have +N.dddE+nnn where length
9477 -- of ddd is determined by type'Digits - 1, but is one
9478 -- if Digits is one (RM 3.5 (33)).
9480 -- nnn is set to 2 for Short_Float and Float (32 bit
9481 -- floats), and 3 for Long_Float and Long_Long_Float.
9482 -- For machines where Long_Long_Float is the IEEE
9483 -- extended precision type, the exponent takes 4 digits.
9487 Int
'Max (2, UI_To_Int
(Digits_Value
(P_Type
)));
9490 if Esize
(P_Type
) <= 32 then
9492 elsif Esize
(P_Type
) = 64 then
9498 Fold_Uint
(N
, UI_From_Int
(Len
), Static
);
9502 -- Fixed-point types
9504 elsif Is_Fixed_Point_Type
(P_Type
) then
9506 -- Width is zero for a null range (RM 3.5 (38))
9508 if Expr_Value
(Type_High_Bound
(P_Type
)) <
9509 Expr_Value
(Type_Low_Bound
(P_Type
))
9511 Fold_Uint
(N
, Uint_0
, Static
);
9513 -- The non-null case depends on the specific real type
9516 -- For fixed-point type width is Fore + 1 + Aft (RM 3.5(34))
9519 (N
, UI_From_Int
(Fore_Value
+ 1) + Aft_Value
(P_Type
),
9527 R
: constant Entity_Id
:= Root_Type
(P_Type
);
9528 Lo
: constant Uint
:= Expr_Value
(Type_Low_Bound
(P_Type
));
9529 Hi
: constant Uint
:= Expr_Value
(Type_High_Bound
(P_Type
));
9542 -- Width for types derived from Standard.Character
9543 -- and Standard.Wide_[Wide_]Character.
9545 elsif Is_Standard_Character_Type
(P_Type
) then
9548 -- Set W larger if needed
9550 for J
in UI_To_Int
(Lo
) .. UI_To_Int
(Hi
) loop
9552 -- All wide characters look like Hex_hhhhhhhh
9556 -- No need to compute this more than once
9561 C
:= Character'Val (J
);
9563 -- Test for all cases where Character'Image
9564 -- yields an image that is longer than three
9565 -- characters. First the cases of Reserved_xxx
9566 -- names (length = 12).
9569 when Reserved_128 | Reserved_129 |
9570 Reserved_132 | Reserved_153
9573 when BS | HT | LF | VT | FF | CR |
9574 SO | SI | EM | FS | GS | RS |
9575 US | RI | MW | ST | PM
9578 when NUL | SOH | STX | ETX | EOT |
9579 ENQ | ACK | BEL | DLE | DC1 |
9580 DC2 | DC3 | DC4 | NAK | SYN |
9581 ETB | CAN | SUB | ESC | DEL |
9582 BPH | NBH | NEL | SSA | ESA |
9583 HTS | HTJ | VTS | PLD | PLU |
9584 SS2 | SS3 | DCS | PU1 | PU2 |
9585 STS | CCH | SPA | EPA | SOS |
9586 SCI | CSI | OSC | APC
9589 when Space
.. Tilde |
9590 No_Break_Space
.. LC_Y_Diaeresis
9592 -- Special case of soft hyphen in Ada 2005
9594 if C
= Character'Val (16#AD#
)
9595 and then Ada_Version
>= Ada_2005
9603 W
:= Int
'Max (W
, Wt
);
9607 -- Width for types derived from Standard.Boolean
9609 elsif R
= Standard_Boolean
then
9616 -- Width for integer types
9618 elsif Is_Integer_Type
(P_Type
) then
9619 T
:= UI_Max
(abs Lo
, abs Hi
);
9627 -- User declared enum type with discard names
9629 elsif Discard_Names
(R
) then
9631 -- If range is null, result is zero, that has already
9632 -- been dealt with, so what we need is the power of ten
9633 -- that accomodates the Pos of the largest value, which
9634 -- is the high bound of the range + one for the space.
9643 -- Only remaining possibility is user declared enum type
9644 -- with normal case of Discard_Names not active.
9647 pragma Assert
(Is_Enumeration_Type
(P_Type
));
9650 L
:= First_Literal
(P_Type
);
9651 while Present
(L
) loop
9653 -- Only pay attention to in range characters
9655 if Lo
<= Enumeration_Pos
(L
)
9656 and then Enumeration_Pos
(L
) <= Hi
9658 -- For Width case, use decoded name
9660 if Id
= Attribute_Width
then
9661 Get_Decoded_Name_String
(Chars
(L
));
9662 Wt
:= Nat
(Name_Len
);
9664 -- For Wide_[Wide_]Width, use encoded name, and
9665 -- then adjust for the encoding.
9668 Get_Name_String
(Chars
(L
));
9670 -- Character literals are always of length 3
9672 if Name_Buffer
(1) = 'Q' then
9675 -- Otherwise loop to adjust for upper/wide chars
9678 Wt
:= Nat
(Name_Len
);
9680 for J
in 1 .. Name_Len
loop
9681 if Name_Buffer
(J
) = 'U' then
9683 elsif Name_Buffer
(J
) = 'W' then
9690 W
:= Int
'Max (W
, Wt
);
9697 Fold_Uint
(N
, UI_From_Int
(W
), Static
);
9703 -- The following attributes denote functions that cannot be folded
9705 when Attribute_From_Any |
9707 Attribute_TypeCode
=>
9710 -- The following attributes can never be folded, and furthermore we
9711 -- should not even have entered the case statement for any of these.
9712 -- Note that in some cases, the values have already been folded as
9713 -- a result of the processing in Analyze_Attribute or earlier in
9716 when Attribute_Abort_Signal |
9719 Attribute_Address_Size |
9720 Attribute_Asm_Input |
9721 Attribute_Asm_Output |
9723 Attribute_Bit_Order |
9724 Attribute_Bit_Position |
9725 Attribute_Callable |
9728 Attribute_Code_Address |
9729 Attribute_Compiler_Version |
9731 Attribute_Default_Bit_Order |
9732 Attribute_Default_Scalar_Storage_Order |
9734 Attribute_Elaborated |
9735 Attribute_Elab_Body |
9736 Attribute_Elab_Spec |
9737 Attribute_Elab_Subp_Body |
9739 Attribute_External_Tag |
9740 Attribute_Fast_Math |
9741 Attribute_First_Bit |
9744 Attribute_Last_Bit |
9745 Attribute_Library_Level |
9746 Attribute_Maximum_Alignment |
9749 Attribute_Partition_ID |
9750 Attribute_Pool_Address |
9751 Attribute_Position |
9752 Attribute_Priority |
9755 Attribute_Scalar_Storage_Order |
9756 Attribute_Simple_Storage_Pool |
9757 Attribute_Storage_Pool |
9758 Attribute_Storage_Size |
9759 Attribute_Storage_Unit |
9760 Attribute_Stub_Type |
9761 Attribute_System_Allocator_Alignment |
9763 Attribute_Target_Name |
9764 Attribute_Terminated |
9765 Attribute_To_Address |
9766 Attribute_Type_Key |
9767 Attribute_Unchecked_Access |
9768 Attribute_Universal_Literal_String |
9769 Attribute_Unrestricted_Access |
9771 Attribute_Valid_Scalars |
9773 Attribute_Wchar_T_Size |
9774 Attribute_Wide_Value |
9775 Attribute_Wide_Wide_Value |
9776 Attribute_Word_Size |
9779 raise Program_Error
;
9782 -- At the end of the case, one more check. If we did a static evaluation
9783 -- so that the result is now a literal, then set Is_Static_Expression
9784 -- in the constant only if the prefix type is a static subtype. For
9785 -- non-static subtypes, the folding is still OK, but not static.
9787 -- An exception is the GNAT attribute Constrained_Array which is
9788 -- defined to be a static attribute in all cases.
9790 if Nkind_In
(N
, N_Integer_Literal
,
9792 N_Character_Literal
,
9794 or else (Is_Entity_Name
(N
)
9795 and then Ekind
(Entity
(N
)) = E_Enumeration_Literal
)
9797 Set_Is_Static_Expression
(N
, Static
);
9799 -- If this is still an attribute reference, then it has not been folded
9800 -- and that means that its expressions are in a non-static context.
9802 elsif Nkind
(N
) = N_Attribute_Reference
then
9805 -- Note: the else case not covered here are odd cases where the
9806 -- processing has transformed the attribute into something other
9807 -- than a constant. Nothing more to do in such cases.
9814 ------------------------------
9815 -- Is_Anonymous_Tagged_Base --
9816 ------------------------------
9818 function Is_Anonymous_Tagged_Base
9820 Typ
: Entity_Id
) return Boolean
9824 Anon
= Current_Scope
9825 and then Is_Itype
(Anon
)
9826 and then Associated_Node_For_Itype
(Anon
) = Parent
(Typ
);
9827 end Is_Anonymous_Tagged_Base
;
9829 --------------------------------
9830 -- Name_Implies_Lvalue_Prefix --
9831 --------------------------------
9833 function Name_Implies_Lvalue_Prefix
(Nam
: Name_Id
) return Boolean is
9834 pragma Assert
(Is_Attribute_Name
(Nam
));
9836 return Attribute_Name_Implies_Lvalue_Prefix
(Get_Attribute_Id
(Nam
));
9837 end Name_Implies_Lvalue_Prefix
;
9839 -----------------------
9840 -- Resolve_Attribute --
9841 -----------------------
9843 procedure Resolve_Attribute
(N
: Node_Id
; Typ
: Entity_Id
) is
9844 Loc
: constant Source_Ptr
:= Sloc
(N
);
9845 P
: constant Node_Id
:= Prefix
(N
);
9846 Aname
: constant Name_Id
:= Attribute_Name
(N
);
9847 Attr_Id
: constant Attribute_Id
:= Get_Attribute_Id
(Aname
);
9848 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
9849 Des_Btyp
: Entity_Id
;
9850 Index
: Interp_Index
;
9852 Nom_Subt
: Entity_Id
;
9854 procedure Accessibility_Message
;
9855 -- Error, or warning within an instance, if the static accessibility
9856 -- rules of 3.10.2 are violated.
9858 function Declared_Within_Generic_Unit
9859 (Entity
: Entity_Id
;
9860 Generic_Unit
: Node_Id
) return Boolean;
9861 -- Returns True if Declared_Entity is declared within the declarative
9862 -- region of Generic_Unit; otherwise returns False.
9864 ---------------------------
9865 -- Accessibility_Message --
9866 ---------------------------
9868 procedure Accessibility_Message
is
9869 Indic
: Node_Id
:= Parent
(Parent
(N
));
9872 -- In an instance, this is a runtime check, but one we
9873 -- know will fail, so generate an appropriate warning.
9875 if In_Instance_Body
then
9876 Error_Msg_Warn
:= SPARK_Mode
/= On
;
9878 ("non-local pointer cannot point to local object<<", P
);
9879 Error_Msg_F
("\Program_Error [<<", P
);
9881 Make_Raise_Program_Error
(Loc
,
9882 Reason
=> PE_Accessibility_Check_Failed
));
9887 Error_Msg_F
("non-local pointer cannot point to local object", P
);
9889 -- Check for case where we have a missing access definition
9891 if Is_Record_Type
(Current_Scope
)
9893 Nkind_In
(Parent
(N
), N_Discriminant_Association
,
9894 N_Index_Or_Discriminant_Constraint
)
9896 Indic
:= Parent
(Parent
(N
));
9897 while Present
(Indic
)
9898 and then Nkind
(Indic
) /= N_Subtype_Indication
9900 Indic
:= Parent
(Indic
);
9903 if Present
(Indic
) then
9905 ("\use an access definition for" &
9906 " the access discriminant of&",
9907 N
, Entity
(Subtype_Mark
(Indic
)));
9911 end Accessibility_Message
;
9913 ----------------------------------
9914 -- Declared_Within_Generic_Unit --
9915 ----------------------------------
9917 function Declared_Within_Generic_Unit
9918 (Entity
: Entity_Id
;
9919 Generic_Unit
: Node_Id
) return Boolean
9921 Generic_Encloser
: Node_Id
:= Enclosing_Generic_Unit
(Entity
);
9924 while Present
(Generic_Encloser
) loop
9925 if Generic_Encloser
= Generic_Unit
then
9929 -- We have to step to the scope of the generic's entity, because
9930 -- otherwise we'll just get back the same generic.
9933 Enclosing_Generic_Unit
9934 (Scope
(Defining_Entity
(Generic_Encloser
)));
9938 end Declared_Within_Generic_Unit
;
9940 -- Start of processing for Resolve_Attribute
9943 -- If error during analysis, no point in continuing, except for array
9944 -- types, where we get better recovery by using unconstrained indexes
9945 -- than nothing at all (see Check_Array_Type).
9948 and then Attr_Id
/= Attribute_First
9949 and then Attr_Id
/= Attribute_Last
9950 and then Attr_Id
/= Attribute_Length
9951 and then Attr_Id
/= Attribute_Range
9956 -- If attribute was universal type, reset to actual type
9958 if Etype
(N
) = Universal_Integer
9959 or else Etype
(N
) = Universal_Real
9964 -- Remaining processing depends on attribute
9972 -- For access attributes, if the prefix denotes an entity, it is
9973 -- interpreted as a name, never as a call. It may be overloaded,
9974 -- in which case resolution uses the profile of the context type.
9975 -- Otherwise prefix must be resolved.
9977 when Attribute_Access
9978 | Attribute_Unchecked_Access
9979 | Attribute_Unrestricted_Access
=>
9983 -- Note possible modification if we have a variable
9985 if Is_Variable
(P
) then
9987 PN
: constant Node_Id
:= Parent
(N
);
9990 Note
: Boolean := True;
9991 -- Skip this for the case of Unrestricted_Access occuring in
9992 -- the context of a Valid check, since this otherwise leads
9993 -- to a missed warning (the Valid check does not really
9994 -- modify!) If this case, Note will be reset to False.
9996 -- Skip it as well if the type is an Acccess_To_Constant,
9997 -- given that no use of the value can modify the prefix.
10000 if Attr_Id
= Attribute_Unrestricted_Access
10001 and then Nkind
(PN
) = N_Function_Call
10005 if Nkind
(Nm
) = N_Expanded_Name
10006 and then Chars
(Nm
) = Name_Valid
10007 and then Nkind
(Prefix
(Nm
)) = N_Identifier
10008 and then Chars
(Prefix
(Nm
)) = Name_Attr_Long_Float
10013 elsif Is_Access_Constant
(Typ
) then
10018 Note_Possible_Modification
(P
, Sure
=> False);
10023 -- The following comes from a query concerning improper use of
10024 -- universal_access in equality tests involving anonymous access
10025 -- types. Another good reason for 'Ref, but for now disable the
10026 -- test, which breaks several filed tests???
10028 if Ekind
(Typ
) = E_Anonymous_Access_Type
10029 and then Nkind_In
(Parent
(N
), N_Op_Eq
, N_Op_Ne
)
10032 Error_Msg_N
("need unique type to resolve 'Access", N
);
10033 Error_Msg_N
("\qualify attribute with some access type", N
);
10036 -- Case where prefix is an entity name
10038 if Is_Entity_Name
(P
) then
10040 -- Deal with case where prefix itself is overloaded
10042 if Is_Overloaded
(P
) then
10043 Get_First_Interp
(P
, Index
, It
);
10044 while Present
(It
.Nam
) loop
10045 if Type_Conformant
(Designated_Type
(Typ
), It
.Nam
) then
10046 Set_Entity
(P
, It
.Nam
);
10048 -- The prefix is definitely NOT overloaded anymore at
10049 -- this point, so we reset the Is_Overloaded flag to
10050 -- avoid any confusion when reanalyzing the node.
10052 Set_Is_Overloaded
(P
, False);
10053 Set_Is_Overloaded
(N
, False);
10054 Generate_Reference
(Entity
(P
), P
);
10058 Get_Next_Interp
(Index
, It
);
10061 -- If Prefix is a subprogram name, this reference freezes:
10063 -- If it is a type, there is nothing to resolve.
10064 -- If it is an object, complete its resolution.
10066 elsif Is_Overloadable
(Entity
(P
)) then
10068 -- Avoid insertion of freeze actions in spec expression mode
10070 if not In_Spec_Expression
then
10071 Freeze_Before
(N
, Entity
(P
));
10074 -- Nothing to do if prefix is a type name
10076 elsif Is_Type
(Entity
(P
)) then
10079 -- Otherwise non-overloaded other case, resolve the prefix
10085 -- Some further error checks
10087 Error_Msg_Name_1
:= Aname
;
10089 if not Is_Entity_Name
(P
) then
10092 elsif Is_Overloadable
(Entity
(P
))
10093 and then Is_Abstract_Subprogram
(Entity
(P
))
10095 Error_Msg_F
("prefix of % attribute cannot be abstract", P
);
10096 Set_Etype
(N
, Any_Type
);
10098 elsif Ekind
(Entity
(P
)) = E_Enumeration_Literal
then
10100 ("prefix of % attribute cannot be enumeration literal", P
);
10101 Set_Etype
(N
, Any_Type
);
10103 -- An attempt to take 'Access of a function that renames an
10104 -- enumeration literal. Issue a specialized error message.
10106 elsif Ekind
(Entity
(P
)) = E_Function
10107 and then Present
(Alias
(Entity
(P
)))
10108 and then Ekind
(Alias
(Entity
(P
))) = E_Enumeration_Literal
10111 ("prefix of % attribute cannot be function renaming "
10112 & "an enumeration literal", P
);
10113 Set_Etype
(N
, Any_Type
);
10115 elsif Convention
(Entity
(P
)) = Convention_Intrinsic
then
10116 Error_Msg_F
("prefix of % attribute cannot be intrinsic", P
);
10117 Set_Etype
(N
, Any_Type
);
10120 -- Assignments, return statements, components of aggregates,
10121 -- generic instantiations will require convention checks if
10122 -- the type is an access to subprogram. Given that there will
10123 -- also be accessibility checks on those, this is where the
10124 -- checks can eventually be centralized ???
10126 if Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
10127 E_Anonymous_Access_Subprogram_Type
,
10128 E_Access_Protected_Subprogram_Type
,
10129 E_Anonymous_Access_Protected_Subprogram_Type
)
10131 -- Deal with convention mismatch
10133 if Convention
(Designated_Type
(Btyp
)) /=
10134 Convention
(Entity
(P
))
10137 ("subprogram & has wrong convention", P
, Entity
(P
));
10138 Error_Msg_Sloc
:= Sloc
(Btyp
);
10139 Error_Msg_FE
("\does not match & declared#", P
, Btyp
);
10141 if not Is_Itype
(Btyp
)
10142 and then not Has_Convention_Pragma
(Btyp
)
10145 ("\probable missing pragma Convention for &",
10150 Check_Subtype_Conformant
10151 (New_Id
=> Entity
(P
),
10152 Old_Id
=> Designated_Type
(Btyp
),
10156 if Attr_Id
= Attribute_Unchecked_Access
then
10157 Error_Msg_Name_1
:= Aname
;
10159 ("attribute% cannot be applied to a subprogram", P
);
10161 elsif Aname
= Name_Unrestricted_Access
then
10162 null; -- Nothing to check
10164 -- Check the static accessibility rule of 3.10.2(32).
10165 -- This rule also applies within the private part of an
10166 -- instantiation. This rule does not apply to anonymous
10167 -- access-to-subprogram types in access parameters.
10169 elsif Attr_Id
= Attribute_Access
10170 and then not In_Instance_Body
10172 (Ekind
(Btyp
) = E_Access_Subprogram_Type
10173 or else Is_Local_Anonymous_Access
(Btyp
))
10174 and then Subprogram_Access_Level
(Entity
(P
)) >
10175 Type_Access_Level
(Btyp
)
10178 ("subprogram must not be deeper than access type", P
);
10180 -- Check the restriction of 3.10.2(32) that disallows the
10181 -- access attribute within a generic body when the ultimate
10182 -- ancestor of the type of the attribute is declared outside
10183 -- of the generic unit and the subprogram is declared within
10184 -- that generic unit. This includes any such attribute that
10185 -- occurs within the body of a generic unit that is a child
10186 -- of the generic unit where the subprogram is declared.
10188 -- The rule also prohibits applying the attribute when the
10189 -- access type is a generic formal access type (since the
10190 -- level of the actual type is not known). This restriction
10191 -- does not apply when the attribute type is an anonymous
10192 -- access-to-subprogram type. Note that this check was
10193 -- revised by AI-229, because the original Ada 95 rule
10194 -- was too lax. The original rule only applied when the
10195 -- subprogram was declared within the body of the generic,
10196 -- which allowed the possibility of dangling references).
10197 -- The rule was also too strict in some cases, in that it
10198 -- didn't permit the access to be declared in the generic
10199 -- spec, whereas the revised rule does (as long as it's not
10202 -- There are a couple of subtleties of the test for applying
10203 -- the check that are worth noting. First, we only apply it
10204 -- when the levels of the subprogram and access type are the
10205 -- same (the case where the subprogram is statically deeper
10206 -- was applied above, and the case where the type is deeper
10207 -- is always safe). Second, we want the check to apply
10208 -- within nested generic bodies and generic child unit
10209 -- bodies, but not to apply to an attribute that appears in
10210 -- the generic unit's specification. This is done by testing
10211 -- that the attribute's innermost enclosing generic body is
10212 -- not the same as the innermost generic body enclosing the
10213 -- generic unit where the subprogram is declared (we don't
10214 -- want the check to apply when the access attribute is in
10215 -- the spec and there's some other generic body enclosing
10216 -- generic). Finally, there's no point applying the check
10217 -- when within an instance, because any violations will have
10218 -- been caught by the compilation of the generic unit.
10220 -- We relax this check in Relaxed_RM_Semantics mode for
10221 -- compatibility with legacy code for use by Ada source
10222 -- code analyzers (e.g. CodePeer).
10224 elsif Attr_Id
= Attribute_Access
10225 and then not Relaxed_RM_Semantics
10226 and then not In_Instance
10227 and then Present
(Enclosing_Generic_Unit
(Entity
(P
)))
10228 and then Present
(Enclosing_Generic_Body
(N
))
10229 and then Enclosing_Generic_Body
(N
) /=
10230 Enclosing_Generic_Body
10231 (Enclosing_Generic_Unit
(Entity
(P
)))
10232 and then Subprogram_Access_Level
(Entity
(P
)) =
10233 Type_Access_Level
(Btyp
)
10234 and then Ekind
(Btyp
) /=
10235 E_Anonymous_Access_Subprogram_Type
10236 and then Ekind
(Btyp
) /=
10237 E_Anonymous_Access_Protected_Subprogram_Type
10239 -- The attribute type's ultimate ancestor must be
10240 -- declared within the same generic unit as the
10241 -- subprogram is declared (including within another
10242 -- nested generic unit). The error message is
10243 -- specialized to say "ancestor" for the case where the
10244 -- access type is not its own ancestor, since saying
10245 -- simply "access type" would be very confusing.
10247 if not Declared_Within_Generic_Unit
10249 Enclosing_Generic_Unit
(Entity
(P
)))
10252 ("''Access attribute not allowed in generic body",
10255 if Root_Type
(Btyp
) = Btyp
then
10258 "access type & is declared outside " &
10259 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10262 ("\because ancestor of " &
10263 "access type & is declared outside " &
10264 "generic unit (RM 3.10.2(32))", N
, Btyp
);
10268 ("\move ''Access to private part, or " &
10269 "(Ada 2005) use anonymous access type instead of &",
10272 -- If the ultimate ancestor of the attribute's type is
10273 -- a formal type, then the attribute is illegal because
10274 -- the actual type might be declared at a higher level.
10275 -- The error message is specialized to say "ancestor"
10276 -- for the case where the access type is not its own
10277 -- ancestor, since saying simply "access type" would be
10280 elsif Is_Generic_Type
(Root_Type
(Btyp
)) then
10281 if Root_Type
(Btyp
) = Btyp
then
10283 ("access type must not be a generic formal type",
10287 ("ancestor access type must not be a generic " &
10294 -- If this is a renaming, an inherited operation, or a
10295 -- subprogram instance, use the original entity. This may make
10296 -- the node type-inconsistent, so this transformation can only
10297 -- be done if the node will not be reanalyzed. In particular,
10298 -- if it is within a default expression, the transformation
10299 -- must be delayed until the default subprogram is created for
10300 -- it, when the enclosing subprogram is frozen.
10302 if Is_Entity_Name
(P
)
10303 and then Is_Overloadable
(Entity
(P
))
10304 and then Present
(Alias
(Entity
(P
)))
10305 and then Expander_Active
10308 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10311 elsif Nkind
(P
) = N_Selected_Component
10312 and then Is_Overloadable
(Entity
(Selector_Name
(P
)))
10314 -- Protected operation. If operation is overloaded, must
10315 -- disambiguate. Prefix that denotes protected object itself
10316 -- is resolved with its own type.
10318 if Attr_Id
= Attribute_Unchecked_Access
then
10319 Error_Msg_Name_1
:= Aname
;
10321 ("attribute% cannot be applied to protected operation", P
);
10324 Resolve
(Prefix
(P
));
10325 Generate_Reference
(Entity
(Selector_Name
(P
)), P
);
10327 -- Implement check implied by 3.10.2 (18.1/2) : F.all'access is
10328 -- statically illegal if F is an anonymous access to subprogram.
10330 elsif Nkind
(P
) = N_Explicit_Dereference
10331 and then Is_Entity_Name
(Prefix
(P
))
10332 and then Ekind
(Etype
(Entity
(Prefix
(P
)))) =
10333 E_Anonymous_Access_Subprogram_Type
10335 Error_Msg_N
("anonymous access to subprogram "
10336 & "has deeper accessibility than any master", P
);
10338 elsif Is_Overloaded
(P
) then
10340 -- Use the designated type of the context to disambiguate
10341 -- Note that this was not strictly conformant to Ada 95,
10342 -- but was the implementation adopted by most Ada 95 compilers.
10343 -- The use of the context type to resolve an Access attribute
10344 -- reference is now mandated in AI-235 for Ada 2005.
10347 Index
: Interp_Index
;
10351 Get_First_Interp
(P
, Index
, It
);
10352 while Present
(It
.Typ
) loop
10353 if Covers
(Designated_Type
(Typ
), It
.Typ
) then
10354 Resolve
(P
, It
.Typ
);
10358 Get_Next_Interp
(Index
, It
);
10365 -- X'Access is illegal if X denotes a constant and the access type
10366 -- is access-to-variable. Same for 'Unchecked_Access. The rule
10367 -- does not apply to 'Unrestricted_Access. If the reference is a
10368 -- default-initialized aggregate component for a self-referential
10369 -- type the reference is legal.
10371 if not (Ekind
(Btyp
) = E_Access_Subprogram_Type
10372 or else Ekind
(Btyp
) = E_Anonymous_Access_Subprogram_Type
10373 or else (Is_Record_Type
(Btyp
)
10375 Present
(Corresponding_Remote_Type
(Btyp
)))
10376 or else Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10377 or else Ekind
(Btyp
)
10378 = E_Anonymous_Access_Protected_Subprogram_Type
10379 or else Is_Access_Constant
(Btyp
)
10380 or else Is_Variable
(P
)
10381 or else Attr_Id
= Attribute_Unrestricted_Access
)
10383 if Is_Entity_Name
(P
)
10384 and then Is_Type
(Entity
(P
))
10386 -- Legality of a self-reference through an access
10387 -- attribute has been verified in Analyze_Access_Attribute.
10391 elsif Comes_From_Source
(N
) then
10392 Error_Msg_F
("access-to-variable designates constant", P
);
10396 Des_Btyp
:= Designated_Type
(Btyp
);
10398 if Ada_Version
>= Ada_2005
10399 and then Is_Incomplete_Type
(Des_Btyp
)
10401 -- Ada 2005 (AI-412): If the (sub)type is a limited view of an
10402 -- imported entity, and the non-limited view is visible, make
10403 -- use of it. If it is an incomplete subtype, use the base type
10406 if From_Limited_With
(Des_Btyp
)
10407 and then Present
(Non_Limited_View
(Des_Btyp
))
10409 Des_Btyp
:= Non_Limited_View
(Des_Btyp
);
10411 elsif Ekind
(Des_Btyp
) = E_Incomplete_Subtype
then
10412 Des_Btyp
:= Etype
(Des_Btyp
);
10416 if (Attr_Id
= Attribute_Access
10418 Attr_Id
= Attribute_Unchecked_Access
)
10419 and then (Ekind
(Btyp
) = E_General_Access_Type
10420 or else Ekind
(Btyp
) = E_Anonymous_Access_Type
)
10422 -- Ada 2005 (AI-230): Check the accessibility of anonymous
10423 -- access types for stand-alone objects, record and array
10424 -- components, and return objects. For a component definition
10425 -- the level is the same of the enclosing composite type.
10427 if Ada_Version
>= Ada_2005
10428 and then (Is_Local_Anonymous_Access
(Btyp
)
10430 -- Handle cases where Btyp is the anonymous access
10431 -- type of an Ada 2012 stand-alone object.
10433 or else Nkind
(Associated_Node_For_Itype
(Btyp
)) =
10434 N_Object_Declaration
)
10436 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10437 and then Attr_Id
= Attribute_Access
10439 -- In an instance, this is a runtime check, but one we know
10440 -- will fail, so generate an appropriate warning. As usual,
10441 -- this kind of warning is an error in SPARK mode.
10443 if In_Instance_Body
then
10444 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10446 ("non-local pointer cannot point to local object<<", P
);
10447 Error_Msg_F
("\Program_Error [<<", P
);
10450 Make_Raise_Program_Error
(Loc
,
10451 Reason
=> PE_Accessibility_Check_Failed
));
10452 Set_Etype
(N
, Typ
);
10456 ("non-local pointer cannot point to local object", P
);
10460 if Is_Dependent_Component_Of_Mutable_Object
(P
) then
10462 ("illegal attribute for discriminant-dependent component",
10466 -- Check static matching rule of 3.10.2(27). Nominal subtype
10467 -- of the prefix must statically match the designated type.
10469 Nom_Subt
:= Etype
(P
);
10471 if Is_Constr_Subt_For_U_Nominal
(Nom_Subt
) then
10472 Nom_Subt
:= Base_Type
(Nom_Subt
);
10475 if Is_Tagged_Type
(Designated_Type
(Typ
)) then
10477 -- If the attribute is in the context of an access
10478 -- parameter, then the prefix is allowed to be of
10479 -- the class-wide type (by AI-127).
10481 if Ekind
(Typ
) = E_Anonymous_Access_Type
then
10482 if not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10483 and then not Covers
(Nom_Subt
, Designated_Type
(Typ
))
10489 Desig
:= Designated_Type
(Typ
);
10491 if Is_Class_Wide_Type
(Desig
) then
10492 Desig
:= Etype
(Desig
);
10495 if Is_Anonymous_Tagged_Base
(Nom_Subt
, Desig
) then
10500 ("type of prefix: & not compatible",
10503 ("\with &, the expected designated type",
10504 P
, Designated_Type
(Typ
));
10509 elsif not Covers
(Designated_Type
(Typ
), Nom_Subt
)
10511 (not Is_Class_Wide_Type
(Designated_Type
(Typ
))
10512 and then Is_Class_Wide_Type
(Nom_Subt
))
10515 ("type of prefix: & is not covered", P
, Nom_Subt
);
10517 ("\by &, the expected designated type" &
10518 " (RM 3.10.2 (27))", P
, Designated_Type
(Typ
));
10521 if Is_Class_Wide_Type
(Designated_Type
(Typ
))
10522 and then Has_Discriminants
(Etype
(Designated_Type
(Typ
)))
10523 and then Is_Constrained
(Etype
(Designated_Type
(Typ
)))
10524 and then Designated_Type
(Typ
) /= Nom_Subt
10526 Apply_Discriminant_Check
10527 (N
, Etype
(Designated_Type
(Typ
)));
10530 -- Ada 2005 (AI-363): Require static matching when designated
10531 -- type has discriminants and a constrained partial view, since
10532 -- in general objects of such types are mutable, so we can't
10533 -- allow the access value to designate a constrained object
10534 -- (because access values must be assumed to designate mutable
10535 -- objects when designated type does not impose a constraint).
10537 elsif Subtypes_Statically_Match
(Des_Btyp
, Nom_Subt
) then
10540 elsif Has_Discriminants
(Designated_Type
(Typ
))
10541 and then not Is_Constrained
(Des_Btyp
)
10543 (Ada_Version
< Ada_2005
10545 not Object_Type_Has_Constrained_Partial_View
10546 (Typ
=> Designated_Type
(Base_Type
(Typ
)),
10547 Scop
=> Current_Scope
))
10553 ("object subtype must statically match "
10554 & "designated subtype", P
);
10556 if Is_Entity_Name
(P
)
10557 and then Is_Array_Type
(Designated_Type
(Typ
))
10560 D
: constant Node_Id
:= Declaration_Node
(Entity
(P
));
10563 ("aliased object has explicit bounds??", D
);
10565 ("\declare without bounds (and with explicit "
10566 & "initialization)??", D
);
10568 ("\for use with unconstrained access??", D
);
10573 -- Check the static accessibility rule of 3.10.2(28). Note that
10574 -- this check is not performed for the case of an anonymous
10575 -- access type, since the access attribute is always legal
10576 -- in such a context.
10578 if Attr_Id
/= Attribute_Unchecked_Access
10579 and then Ekind
(Btyp
) = E_General_Access_Type
10581 Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10583 Accessibility_Message
;
10588 if Ekind_In
(Btyp
, E_Access_Protected_Subprogram_Type
,
10589 E_Anonymous_Access_Protected_Subprogram_Type
)
10591 if Is_Entity_Name
(P
)
10592 and then not Is_Protected_Type
(Scope
(Entity
(P
)))
10594 Error_Msg_F
("context requires a protected subprogram", P
);
10596 -- Check accessibility of protected object against that of the
10597 -- access type, but only on user code, because the expander
10598 -- creates access references for handlers. If the context is an
10599 -- anonymous_access_to_protected, there are no accessibility
10600 -- checks either. Omit check entirely for Unrestricted_Access.
10602 elsif Object_Access_Level
(P
) > Deepest_Type_Access_Level
(Btyp
)
10603 and then Comes_From_Source
(N
)
10604 and then Ekind
(Btyp
) = E_Access_Protected_Subprogram_Type
10605 and then Attr_Id
/= Attribute_Unrestricted_Access
10607 Accessibility_Message
;
10610 -- AI05-0225: If the context is not an access to protected
10611 -- function, the prefix must be a variable, given that it may
10612 -- be used subsequently in a protected call.
10614 elsif Nkind
(P
) = N_Selected_Component
10615 and then not Is_Variable
(Prefix
(P
))
10616 and then Ekind
(Entity
(Selector_Name
(P
))) /= E_Function
10619 ("target object of access to protected procedure "
10620 & "must be variable", N
);
10622 elsif Is_Entity_Name
(P
) then
10623 Check_Internal_Protected_Use
(N
, Entity
(P
));
10626 elsif Ekind_In
(Btyp
, E_Access_Subprogram_Type
,
10627 E_Anonymous_Access_Subprogram_Type
)
10628 and then Ekind
(Etype
(N
)) = E_Access_Protected_Subprogram_Type
10630 Error_Msg_F
("context requires a non-protected subprogram", P
);
10633 -- The context cannot be a pool-specific type, but this is a
10634 -- legality rule, not a resolution rule, so it must be checked
10635 -- separately, after possibly disambiguation (see AI-245).
10637 if Ekind
(Btyp
) = E_Access_Type
10638 and then Attr_Id
/= Attribute_Unrestricted_Access
10640 Wrong_Type
(N
, Typ
);
10643 -- The context may be a constrained access type (however ill-
10644 -- advised such subtypes might be) so in order to generate a
10645 -- constraint check when needed set the type of the attribute
10646 -- reference to the base type of the context.
10648 Set_Etype
(N
, Btyp
);
10650 -- Check for incorrect atomic/volatile reference (RM C.6(12))
10652 if Attr_Id
/= Attribute_Unrestricted_Access
then
10653 if Is_Atomic_Object
(P
)
10654 and then not Is_Atomic
(Designated_Type
(Typ
))
10657 ("access to atomic object cannot yield access-to-" &
10658 "non-atomic type", P
);
10660 elsif Is_Volatile_Object
(P
)
10661 and then not Is_Volatile
(Designated_Type
(Typ
))
10664 ("access to volatile object cannot yield access-to-" &
10665 "non-volatile type", P
);
10669 -- Check for unrestricted access where expected type is a thin
10670 -- pointer to an unconstrained array.
10672 if Non_Aliased_Prefix
(N
)
10673 and then Has_Size_Clause
(Typ
)
10674 and then RM_Size
(Typ
) = System_Address_Size
10677 DT
: constant Entity_Id
:= Designated_Type
(Typ
);
10679 if Is_Array_Type
(DT
) and then not Is_Constrained
(DT
) then
10681 ("illegal use of Unrestricted_Access attribute", P
);
10683 ("\attempt to generate thin pointer to unaliased "
10689 -- Mark that address of entity is taken
10691 if Is_Entity_Name
(P
) then
10692 Set_Address_Taken
(Entity
(P
));
10695 -- Deal with possible elaboration check
10697 if Is_Entity_Name
(P
) and then Is_Subprogram
(Entity
(P
)) then
10699 Subp_Id
: constant Entity_Id
:= Entity
(P
);
10700 Scop
: constant Entity_Id
:= Scope
(Subp_Id
);
10701 Subp_Decl
: constant Node_Id
:=
10702 Unit_Declaration_Node
(Subp_Id
);
10703 Flag_Id
: Entity_Id
;
10704 Subp_Body
: Node_Id
;
10706 -- If the access has been taken and the body of the subprogram
10707 -- has not been see yet, indirect calls must be protected with
10708 -- elaboration checks. We have the proper elaboration machinery
10709 -- for subprograms declared in packages, but within a block or
10710 -- a subprogram the body will appear in the same declarative
10711 -- part, and we must insert a check in the eventual body itself
10712 -- using the elaboration flag that we generate now. The check
10713 -- is then inserted when the body is expanded. This processing
10714 -- is not needed for a stand alone expression function because
10715 -- the internally generated spec and body are always inserted
10716 -- as a pair in the same declarative list.
10720 and then Comes_From_Source
(Subp_Id
)
10721 and then Comes_From_Source
(N
)
10722 and then In_Open_Scopes
(Scop
)
10723 and then Ekind_In
(Scop
, E_Block
, E_Procedure
, E_Function
)
10724 and then not Has_Completion
(Subp_Id
)
10725 and then No
(Elaboration_Entity
(Subp_Id
))
10726 and then Nkind
(Subp_Decl
) = N_Subprogram_Declaration
10727 and then Nkind
(Original_Node
(Subp_Decl
)) /=
10728 N_Expression_Function
10730 -- Create elaboration variable for it
10732 Flag_Id
:= Make_Temporary
(Loc
, 'E');
10733 Set_Elaboration_Entity
(Subp_Id
, Flag_Id
);
10734 Set_Is_Frozen
(Flag_Id
);
10736 -- Insert declaration for flag after subprogram
10737 -- declaration. Note that attribute reference may
10738 -- appear within a nested scope.
10740 Insert_After_And_Analyze
(Subp_Decl
,
10741 Make_Object_Declaration
(Loc
,
10742 Defining_Identifier
=> Flag_Id
,
10743 Object_Definition
=>
10744 New_Occurrence_Of
(Standard_Short_Integer
, Loc
),
10746 Make_Integer_Literal
(Loc
, Uint_0
)));
10749 -- Taking the 'Access of an expression function freezes its
10750 -- expression (RM 13.14 10.3/3). This does not apply to an
10751 -- expression function that acts as a completion because the
10752 -- generated body is immediately analyzed and the expression
10753 -- is automatically frozen.
10755 if Is_Expression_Function
(Subp_Id
)
10756 and then Present
(Corresponding_Body
(Subp_Decl
))
10759 Unit_Declaration_Node
(Corresponding_Body
(Subp_Decl
));
10761 -- The body has already been analyzed when the expression
10762 -- function acts as a completion.
10764 if Analyzed
(Subp_Body
) then
10767 -- Attribute 'Access may appear within the generated body
10768 -- of the expression function subject to the attribute:
10770 -- function F is (... F'Access ...);
10772 -- If the expression function is on the scope stack, then
10773 -- the body is currently being analyzed. Do not reanalyze
10774 -- it because this will lead to infinite recursion.
10776 elsif In_Open_Scopes
(Subp_Id
) then
10779 -- If reference to the expression function appears in an
10780 -- inner scope, for example as an actual in an instance,
10781 -- this is not a freeze point either.
10783 elsif Scope
(Subp_Id
) /= Current_Scope
then
10786 -- Analyze the body of the expression function to freeze
10787 -- the expression. This takes care of the case where the
10788 -- 'Access is part of dispatch table initialization and
10789 -- the generated body of the expression function has not
10790 -- been analyzed yet.
10793 Analyze
(Subp_Body
);
10798 end Access_Attribute
;
10804 -- Deal with resolving the type for Address attribute, overloading
10805 -- is not permitted here, since there is no context to resolve it.
10807 when Attribute_Address | Attribute_Code_Address
=>
10808 Address_Attribute
: begin
10810 -- To be safe, assume that if the address of a variable is taken,
10811 -- it may be modified via this address, so note modification.
10813 if Is_Variable
(P
) then
10814 Note_Possible_Modification
(P
, Sure
=> False);
10817 if Nkind
(P
) in N_Subexpr
10818 and then Is_Overloaded
(P
)
10820 Get_First_Interp
(P
, Index
, It
);
10821 Get_Next_Interp
(Index
, It
);
10823 if Present
(It
.Nam
) then
10824 Error_Msg_Name_1
:= Aname
;
10826 ("prefix of % attribute cannot be overloaded", P
);
10830 if not Is_Entity_Name
(P
)
10831 or else not Is_Overloadable
(Entity
(P
))
10833 if not Is_Task_Type
(Etype
(P
))
10834 or else Nkind
(P
) = N_Explicit_Dereference
10840 -- If this is the name of a derived subprogram, or that of a
10841 -- generic actual, the address is that of the original entity.
10843 if Is_Entity_Name
(P
)
10844 and then Is_Overloadable
(Entity
(P
))
10845 and then Present
(Alias
(Entity
(P
)))
10848 New_Occurrence_Of
(Alias
(Entity
(P
)), Sloc
(P
)));
10851 if Is_Entity_Name
(P
) then
10852 Set_Address_Taken
(Entity
(P
));
10855 if Nkind
(P
) = N_Slice
then
10857 -- Arr (X .. Y)'address is identical to Arr (X)'address,
10858 -- even if the array is packed and the slice itself is not
10859 -- addressable. Transform the prefix into an indexed component.
10861 -- Note that the transformation is safe only if we know that
10862 -- the slice is non-null. That is because a null slice can have
10863 -- an out of bounds index value.
10865 -- Right now, gigi blows up if given 'Address on a slice as a
10866 -- result of some incorrect freeze nodes generated by the front
10867 -- end, and this covers up that bug in one case, but the bug is
10868 -- likely still there in the cases not handled by this code ???
10870 -- It's not clear what 'Address *should* return for a null
10871 -- slice with out of bounds indexes, this might be worth an ARG
10874 -- One approach would be to do a length check unconditionally,
10875 -- and then do the transformation below unconditionally, but
10876 -- analyze with checks off, avoiding the problem of the out of
10877 -- bounds index. This approach would interpret the address of
10878 -- an out of bounds null slice as being the address where the
10879 -- array element would be if there was one, which is probably
10880 -- as reasonable an interpretation as any ???
10883 Loc
: constant Source_Ptr
:= Sloc
(P
);
10884 D
: constant Node_Id
:= Discrete_Range
(P
);
10888 if Is_Entity_Name
(D
)
10891 (Type_Low_Bound
(Entity
(D
)),
10892 Type_High_Bound
(Entity
(D
)))
10895 Make_Attribute_Reference
(Loc
,
10896 Prefix
=> (New_Occurrence_Of
(Entity
(D
), Loc
)),
10897 Attribute_Name
=> Name_First
);
10899 elsif Nkind
(D
) = N_Range
10900 and then Not_Null_Range
(Low_Bound
(D
), High_Bound
(D
))
10902 Lo
:= Low_Bound
(D
);
10908 if Present
(Lo
) then
10910 Make_Indexed_Component
(Loc
,
10911 Prefix
=> Relocate_Node
(Prefix
(P
)),
10912 Expressions
=> New_List
(Lo
)));
10914 Analyze_And_Resolve
(P
);
10918 end Address_Attribute
;
10924 -- Prefix of Body_Version attribute can be a subprogram name which
10925 -- must not be resolved, since this is not a call.
10927 when Attribute_Body_Version
=>
10934 -- Prefix of Caller attribute is an entry name which must not
10935 -- be resolved, since this is definitely not an entry call.
10937 when Attribute_Caller
=>
10944 -- Shares processing with Address attribute
10950 -- If the prefix of the Count attribute is an entry name it must not
10951 -- be resolved, since this is definitely not an entry call. However,
10952 -- if it is an element of an entry family, the index itself may
10953 -- have to be resolved because it can be a general expression.
10955 when Attribute_Count
=>
10956 if Nkind
(P
) = N_Indexed_Component
10957 and then Is_Entity_Name
(Prefix
(P
))
10960 Indx
: constant Node_Id
:= First
(Expressions
(P
));
10961 Fam
: constant Entity_Id
:= Entity
(Prefix
(P
));
10963 Resolve
(Indx
, Entry_Index_Type
(Fam
));
10964 Apply_Range_Check
(Indx
, Entry_Index_Type
(Fam
));
10972 -- Prefix of the Elaborated attribute is a subprogram name which
10973 -- must not be resolved, since this is definitely not a call. Note
10974 -- that it is a library unit, so it cannot be overloaded here.
10976 when Attribute_Elaborated
=>
10983 -- Prefix of Enabled attribute is a check name, which must be treated
10984 -- specially and not touched by Resolve.
10986 when Attribute_Enabled
=>
10993 -- Do not resolve the prefix of Loop_Entry, instead wait until the
10994 -- attribute has been expanded (see Expand_Loop_Entry_Attributes).
10995 -- The delay ensures that any generated checks or temporaries are
10996 -- inserted before the relocated prefix.
10998 when Attribute_Loop_Entry
=>
11001 --------------------
11002 -- Mechanism_Code --
11003 --------------------
11005 -- Prefix of the Mechanism_Code attribute is a function name
11006 -- which must not be resolved. Should we check for overloaded ???
11008 when Attribute_Mechanism_Code
=>
11015 -- Most processing is done in sem_dist, after determining the
11016 -- context type. Node is rewritten as a conversion to a runtime call.
11018 when Attribute_Partition_ID
=>
11019 Process_Partition_Id
(N
);
11026 when Attribute_Pool_Address
=>
11033 -- We replace the Range attribute node with a range expression whose
11034 -- bounds are the 'First and 'Last attributes applied to the same
11035 -- prefix. The reason that we do this transformation here instead of
11036 -- in the expander is that it simplifies other parts of the semantic
11037 -- analysis which assume that the Range has been replaced; thus it
11038 -- must be done even when in semantic-only mode (note that the RM
11039 -- specifically mentions this equivalence, we take care that the
11040 -- prefix is only evaluated once).
11042 when Attribute_Range
=> Range_Attribute
:
11049 if not Is_Entity_Name
(P
)
11050 or else not Is_Type
(Entity
(P
))
11055 Dims
:= Expressions
(N
);
11058 Make_Attribute_Reference
(Loc
,
11059 Prefix
=> Duplicate_Subexpr
(P
, Name_Req
=> True),
11060 Attribute_Name
=> Name_Last
,
11061 Expressions
=> Dims
);
11064 Make_Attribute_Reference
(Loc
,
11066 Attribute_Name
=> Name_First
,
11067 Expressions
=> (Dims
));
11069 -- Do not share the dimension indicator, if present. Even
11070 -- though it is a static constant, its source location
11071 -- may be modified when printing expanded code and node
11072 -- sharing will lead to chaos in Sprint.
11074 if Present
(Dims
) then
11075 Set_Expressions
(LB
,
11076 New_List
(New_Copy_Tree
(First
(Dims
))));
11079 -- If the original was marked as Must_Not_Freeze (see code
11080 -- in Sem_Ch3.Make_Index), then make sure the rewriting
11081 -- does not freeze either.
11083 if Must_Not_Freeze
(N
) then
11084 Set_Must_Not_Freeze
(HB
);
11085 Set_Must_Not_Freeze
(LB
);
11086 Set_Must_Not_Freeze
(Prefix
(HB
));
11087 Set_Must_Not_Freeze
(Prefix
(LB
));
11090 if Raises_Constraint_Error
(Prefix
(N
)) then
11092 -- Preserve Sloc of prefix in the new bounds, so that
11093 -- the posted warning can be removed if we are within
11094 -- unreachable code.
11096 Set_Sloc
(LB
, Sloc
(Prefix
(N
)));
11097 Set_Sloc
(HB
, Sloc
(Prefix
(N
)));
11100 Rewrite
(N
, Make_Range
(Loc
, LB
, HB
));
11101 Analyze_And_Resolve
(N
, Typ
);
11103 -- Ensure that the expanded range does not have side effects
11105 Force_Evaluation
(LB
);
11106 Force_Evaluation
(HB
);
11108 -- Normally after resolving attribute nodes, Eval_Attribute
11109 -- is called to do any possible static evaluation of the node.
11110 -- However, here since the Range attribute has just been
11111 -- transformed into a range expression it is no longer an
11112 -- attribute node and therefore the call needs to be avoided
11113 -- and is accomplished by simply returning from the procedure.
11116 end Range_Attribute
;
11122 -- We will only come here during the prescan of a spec expression
11123 -- containing a Result attribute. In that case the proper Etype has
11124 -- already been set, and nothing more needs to be done here.
11126 when Attribute_Result
=>
11129 ----------------------
11130 -- Unchecked_Access --
11131 ----------------------
11133 -- Processing is shared with Access
11135 -------------------------
11136 -- Unrestricted_Access --
11137 -------------------------
11139 -- Processing is shared with Access
11145 -- Resolve aggregate components in component associations
11147 when Attribute_Update
=>
11149 Aggr
: constant Node_Id
:= First
(Expressions
(N
));
11150 Typ
: constant Entity_Id
:= Etype
(Prefix
(N
));
11156 -- Set the Etype of the aggregate to that of the prefix, even
11157 -- though the aggregate may not be a proper representation of a
11158 -- value of the type (missing or duplicated associations, etc.)
11159 -- Complete resolution of the prefix. Note that in Ada 2012 it
11160 -- can be a qualified expression that is e.g. an aggregate.
11162 Set_Etype
(Aggr
, Typ
);
11163 Resolve
(Prefix
(N
), Typ
);
11165 -- For an array type, resolve expressions with the component
11166 -- type of the array, and apply constraint checks when needed.
11168 if Is_Array_Type
(Typ
) then
11169 Assoc
:= First
(Component_Associations
(Aggr
));
11170 while Present
(Assoc
) loop
11171 Expr
:= Expression
(Assoc
);
11172 Resolve
(Expr
, Component_Type
(Typ
));
11174 -- For scalar array components set Do_Range_Check when
11175 -- needed. Constraint checking on non-scalar components
11176 -- is done in Aggregate_Constraint_Checks, but only if
11177 -- full analysis is enabled. These flags are not set in
11178 -- the front-end in GnatProve mode.
11180 if Is_Scalar_Type
(Component_Type
(Typ
))
11181 and then not Is_OK_Static_Expression
(Expr
)
11183 if Is_Entity_Name
(Expr
)
11184 and then Etype
(Expr
) = Component_Type
(Typ
)
11189 Set_Do_Range_Check
(Expr
);
11193 -- The choices in the association are static constants,
11194 -- or static aggregates each of whose components belongs
11195 -- to the proper index type. However, they must also
11196 -- belong to the index subtype (s) of the prefix, which
11197 -- may be a subtype (e.g. given by a slice).
11199 -- Choices may also be identifiers with no staticness
11200 -- requirements, in which case they must resolve to the
11209 C
:= First
(Choices
(Assoc
));
11210 while Present
(C
) loop
11211 Indx
:= First_Index
(Etype
(Prefix
(N
)));
11213 if Nkind
(C
) /= N_Aggregate
then
11214 Analyze_And_Resolve
(C
, Etype
(Indx
));
11215 Apply_Constraint_Check
(C
, Etype
(Indx
));
11216 Check_Non_Static_Context
(C
);
11219 C_E
:= First
(Expressions
(C
));
11220 while Present
(C_E
) loop
11221 Analyze_And_Resolve
(C_E
, Etype
(Indx
));
11222 Apply_Constraint_Check
(C_E
, Etype
(Indx
));
11223 Check_Non_Static_Context
(C_E
);
11237 -- For a record type, use type of each component, which is
11238 -- recorded during analysis.
11241 Assoc
:= First
(Component_Associations
(Aggr
));
11242 while Present
(Assoc
) loop
11243 Comp
:= First
(Choices
(Assoc
));
11244 Expr
:= Expression
(Assoc
);
11246 if Nkind
(Comp
) /= N_Others_Choice
11247 and then not Error_Posted
(Comp
)
11249 Resolve
(Expr
, Etype
(Entity
(Comp
)));
11251 if Is_Scalar_Type
(Etype
(Entity
(Comp
)))
11252 and then not Is_OK_Static_Expression
(Expr
)
11254 Set_Do_Range_Check
(Expr
);
11267 -- Apply range check. Note that we did not do this during the
11268 -- analysis phase, since we wanted Eval_Attribute to have a
11269 -- chance at finding an illegal out of range value.
11271 when Attribute_Val
=>
11273 -- Note that we do our own Eval_Attribute call here rather than
11274 -- use the common one, because we need to do processing after
11275 -- the call, as per above comment.
11277 Eval_Attribute
(N
);
11279 -- Eval_Attribute may replace the node with a raise CE, or
11280 -- fold it to a constant. Obviously we only apply a scalar
11281 -- range check if this did not happen.
11283 if Nkind
(N
) = N_Attribute_Reference
11284 and then Attribute_Name
(N
) = Name_Val
11286 Apply_Scalar_Range_Check
(First
(Expressions
(N
)), Btyp
);
11295 -- Prefix of Version attribute can be a subprogram name which
11296 -- must not be resolved, since this is not a call.
11298 when Attribute_Version
=>
11301 ----------------------
11302 -- Other Attributes --
11303 ----------------------
11305 -- For other attributes, resolve prefix unless it is a type. If
11306 -- the attribute reference itself is a type name ('Base and 'Class)
11307 -- then this is only legal within a task or protected record.
11310 if not Is_Entity_Name
(P
) or else not Is_Type
(Entity
(P
)) then
11314 -- If the attribute reference itself is a type name ('Base,
11315 -- 'Class) then this is only legal within a task or protected
11316 -- record. What is this all about ???
11318 if Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
11319 if Is_Concurrent_Type
(Entity
(N
))
11320 and then In_Open_Scopes
(Entity
(P
))
11325 ("invalid use of subtype name in expression or call", N
);
11329 -- For attributes whose argument may be a string, complete
11330 -- resolution of argument now. This avoids premature expansion
11331 -- (and the creation of transient scopes) before the attribute
11332 -- reference is resolved.
11335 when Attribute_Value
=>
11336 Resolve
(First
(Expressions
(N
)), Standard_String
);
11338 when Attribute_Wide_Value
=>
11339 Resolve
(First
(Expressions
(N
)), Standard_Wide_String
);
11341 when Attribute_Wide_Wide_Value
=>
11342 Resolve
(First
(Expressions
(N
)), Standard_Wide_Wide_String
);
11344 when others => null;
11347 -- If the prefix of the attribute is a class-wide type then it
11348 -- will be expanded into a dispatching call to a predefined
11349 -- primitive. Therefore we must check for potential violation
11350 -- of such restriction.
11352 if Is_Class_Wide_Type
(Etype
(P
)) then
11353 Check_Restriction
(No_Dispatching_Calls
, N
);
11357 -- Normally the Freezing is done by Resolve but sometimes the Prefix
11358 -- is not resolved, in which case the freezing must be done now.
11360 -- For an elaboration check on a subprogram, we do not freeze its type.
11361 -- It may be declared in an unrelated scope, in particular in the case
11362 -- of a generic function whose type may remain unelaborated.
11364 if Attr_Id
= Attribute_Elaborated
then
11368 Freeze_Expression
(P
);
11371 -- Finally perform static evaluation on the attribute reference
11373 Analyze_Dimension
(N
);
11374 Eval_Attribute
(N
);
11375 end Resolve_Attribute
;
11377 ------------------------
11378 -- Set_Boolean_Result --
11379 ------------------------
11381 procedure Set_Boolean_Result
(N
: Node_Id
; B
: Boolean) is
11382 Loc
: constant Source_Ptr
:= Sloc
(N
);
11385 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
11387 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
11389 end Set_Boolean_Result
;
11391 --------------------------------
11392 -- Stream_Attribute_Available --
11393 --------------------------------
11395 function Stream_Attribute_Available
11397 Nam
: TSS_Name_Type
;
11398 Partial_View
: Node_Id
:= Empty
) return Boolean
11400 Etyp
: Entity_Id
:= Typ
;
11402 -- Start of processing for Stream_Attribute_Available
11405 -- We need some comments in this body ???
11407 if Has_Stream_Attribute_Definition
(Typ
, Nam
) then
11411 if Is_Class_Wide_Type
(Typ
) then
11412 return not Is_Limited_Type
(Typ
)
11413 or else Stream_Attribute_Available
(Etype
(Typ
), Nam
);
11416 if Nam
= TSS_Stream_Input
11417 and then Is_Abstract_Type
(Typ
)
11418 and then not Is_Class_Wide_Type
(Typ
)
11423 if not (Is_Limited_Type
(Typ
)
11424 or else (Present
(Partial_View
)
11425 and then Is_Limited_Type
(Partial_View
)))
11430 -- In Ada 2005, Input can invoke Read, and Output can invoke Write
11432 if Nam
= TSS_Stream_Input
11433 and then Ada_Version
>= Ada_2005
11434 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Read
)
11438 elsif Nam
= TSS_Stream_Output
11439 and then Ada_Version
>= Ada_2005
11440 and then Stream_Attribute_Available
(Etyp
, TSS_Stream_Write
)
11445 -- Case of Read and Write: check for attribute definition clause that
11446 -- applies to an ancestor type.
11448 while Etype
(Etyp
) /= Etyp
loop
11449 Etyp
:= Etype
(Etyp
);
11451 if Has_Stream_Attribute_Definition
(Etyp
, Nam
) then
11456 if Ada_Version
< Ada_2005
then
11458 -- In Ada 95 mode, also consider a non-visible definition
11461 Btyp
: constant Entity_Id
:= Implementation_Base_Type
(Typ
);
11464 and then Stream_Attribute_Available
11465 (Btyp
, Nam
, Partial_View
=> Typ
);
11470 end Stream_Attribute_Available
;